The effects of diabetes clubs on peer-support, disclosure of diabetes status, and sources of information regarding diabetes management: results of a pilot-intervention in rural Vietnam

OBJECTIVES

To measure the effects of diabetes clubs on peer support, disclosure of diabetes status, and the source of information regarding the management of diabetes among persons living with type-2 diabetes (T2D) in rural Vietnam.

STUDY DESIGN

A pre- and post-pilot intervention study was carried out in Thai Binh Province, Vietnam (n = 222).

RESULTS

Post-intervention, 57.7 % reported using experiences shared by other persons with T2D during the diabetes club sessions. Compared to pre-intervention, there was an increase in the proportion of persons with T2D who disclosed their diabetes status to friends and/or community members (an increase of 15.3 and 13.8 percentage points, respectively). The proportion of persons who reported gathering their own information regarding diabetes management without any support from others decreased from 15.7 % to 6.3 %. Those who reported a relative inside their home or a relative outside their household as their primary source of T2D-relevant information increased from 10.8 % to 18.6 % and from 2.7 % to 9.5 %, respectively. Persons who mentioned that they did not have a need for further support for their diabetes care increased from 18.5 % to 32.0 %. Specific support regarding diabetes-related knowledge received from family members, friends, and/or community members increased from 27.5 % to 62.2 % CONCLUSIONS: These findings suggest a promising potential for the implementation of diabetes clubs to enhance diabetes-relevant knowledge and the quality of self-management among persons living with T2D diabetes in rural areas of Vietnam.

Ethical dilemmas in conducting qualitative, public health research on social media: using a study on Facebook as a case

AIM

Platforms on social media are increasingly used for public health research. While social media provides an exceptional opportunity to explore communication about public health topics, this practice is not without ethical dilemmas. Our aim was to identify and unfold some of these dilemmas and to suggest possible solutions and ways forward for future research.

METHODS

Using our own research within a closed forum for people experiencing suicidal thoughts as a case, we explored certain dilemmas and possible answers relating to whether what is to be researched falls under a public or private social media domain; we investigated avenues for obtaining access to participants in an evolving online environment; how to secure informed consent from participants; and ways of ensuring anonymity.

RESULTS

We provide recommendations and reflections that we hope will offer inspiration for researchers embarking on similar social media public health research within and beyond suicide research.

CONCLUSIONS

The ethical framework commonly referred to in health research, based on confidentiality, anonymity, informed consent and doing no harm must be adjusted to be relevant for a social media context where technologies and regulations are constantly being altered.

Pre-/-post-analyses of a feasibility study of a peer-based club intervention among people living with type 2 diabetes in Vietnam's rural communities

OBJECTIVES

Insufficient self-management is a significant barrier for people with type 2 diabetes (T2D) to achieve glycemic control and consequently reduce the risk of acute and long-term diabetes complications, negatively affecting their quality of life and increasing their risk of diabetes-related death. This pre-post study aimed to evaluate whether a peer-based club intervention might reduce glycated hemoglobin from baseline to post-intervention and enhance self-management among people living with T2D in two rural communities in Vietnam.

METHODS

A pre-post study was implemented with 222 adults with T2D residing in two rural communities in Vietnam. We used a structured questionnaire, clinical examination, and glycated hemoglobin to evaluate the possible effects of a diabetes club intervention by comparing Glycated Hemoglobin (HbA1c), Body Mass Index (BMI), Blood Pressure (BP), and diabetes-related self-management behaviors at baseline and post-intervention. The data were analyzed using SPSS 20, applying two related sample tests (Wilcoxon and McNemar test) and a paired-sample t-test at a significance level of less than 0.05.

RESULTS

The findings indicated that after implementation of the intervention, there were no significant statistical differences when comparing pre-and post-intervention levels of the primary outcome HbA1c, but some components of diabetes self-management showed statistically significant improvement.

CONCLUSIONS

After the peer support intervention in a Vietnamese rural community, there was no significant reduction in the primary outcome proportion of patients having an HbA1c less than 7%, but foot care knowledge and practice had improved.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05602441.

Risk of stillbirth and preterm birth among undocumented pregnant migrant women in Denmark: A retrospective case-control study

AIMS

To examine the associations between undocumented pregnant migrant women and the risk of experiencing stillbirth or preterm birth.

METHODS

A retrospective case-control study based on nationwide registers from Statistics Denmark and hospital journals from the seven largest hospital wards in Denmark from 1 January 2011 to 31 December 2018. A total of 882 undocumented pregnant migrant women and 3528 matched controls (both documented migrant and non-migrant women) were included. Logistic regression models were used to estimate the risk of undocumented pregnant migrant women experiencing (a) stillbirth and (b) preterm birth compared with the control group.

RESULTS

Of the undocumented pregnant migrant women, 33.3% were EU citizens, 16.2% were applicants for residence and 50.5% had an unknown basis for residence. The mean age of the undocumented pregnant migrant women was 28.4 years, whereas the mean age of women in the control group was 30.9 years. Higher adjusted odds of experiencing stillbirth (aOR 3.50; 95% CI 1.31-9.38) and preterm birth (aOR 1.41; 95% CI 1.04-1.93) were observed among the undocumented pregnant migrant women compared with the control group. The basis of residence was not associated with higher odds of experiencing stillbirth or preterm birth.

CONCLUSIONS

We found a higher risk of stillbirth and preterm birth among the undocumented pregnant migrant women than in the control group. Our findings suggest a need to increase the focus on providing access to antenatal care among those women currently excluded from this care.

Socio-cognitive factors influencing access to HIV prevention services among people who inject drugs in Dar es Salaam, Tanzania: An integrated bio-behavioural survey

Introduction

People who inject drugs (PWID) in Sub-Saharan Africa have limited access to comprehensive HIV services. While it is important to inform programming, knowledge about factors influencing access to comprehensive HIV services is scarce. We assessed the proportions of PWID with access to HIV prevention services and associated socio-cognitive factors in Tanzania.

Methods

A cross-sectional survey was conducted among PWID between October and December 2017 in Dar es Salaam, Tanzania. Data on access to HIV prevention services, demographics and selected socio-cognitive factors were collected through structured face-to-face interviews. Weighted descriptive and forward selection multivariable logistics regression analyses were done to assess independent associations between HIV prevention services and predictors of interest. The results were two tailed and a p-value of less than 0.05 was considered statistically significant.

Results

The study included 611 PWID (males: 94.4%) with a median age of 34 years (Interquartile Range (IQR), 29–38). A large majority of participants reported to have access to condoms (87.8%), sterile needles/syringes (72.8%) and ever tested for HIV (66.0%). About half (52.0%) reported to have used condoms in the past one month and about a third (28.5%) accessed a peer educator. The odds of testing for HIV decreased among participants who perceived their HIV risk to be high (aOR = 0.29; 95%CI: 0.17–0.49) and those experienced sexual violence (aOR = 0.60; 95%CI 0.37–0.98). However, the odds of testing for HIV increased among participants with secondary level of education (aOR = 2.16; 95%CI: 1.06–5.55), and those who reported having correct comprehensive HIV knowledge (CCHK) (aOR = 1.63; 95%CI 1.12–2.41). The odds of access to condoms increased among females (aOR = 2.23; 95%CI: 1.04–5.02) but decreased among participants with secondary level of education (aOR = 0.41; 95%CI: 0.19–0.84), an income of >TZS 200,000 (aOR = 0.39; 95%CI: 0.23–0.66) and those who perceived their HIV risk to be high (aOR = 0.13; 95%CI: 0.03–0.36). The odds of access to peer educators was higher among participants with primary (aOR = 1.61; 95%CI: 1.01–2.26), and secondary (aOR = 2.71; 95%CI: 1.39–5.33) levels of education. The odds of access to sterile needle and syringe decreased among participants who perceived their HIV risk to be high (aOR = 0.11;95%CI 0.05–0.22), and low-medium (aOR = 0.25;95%CI 0.11–0.52) but increased among those with primary level of education (aOR = 1.72;95%CI 1.06–2.78).

Conclusion

Access to condom, HIV testing, sterile needles and syringes were relatively high among PWID. However, condom use and access to peer educators was relatively low. HIV knowledge and risk perception, gender, education, and sexual violence influenced access to HIV prevention services. There is an urgent need to address the identified socio-cognitive factors and scale up all aspects of HIV prevention services to fast-track attainment of the 2025 UNAIDS goals and ending the HIV epidemic.

Learning from changes concurrent with implementing a complex and dynamic intervention to improve urban maternal and perinatal health in Dar es Salaam, Tanzania, 2011-2019

Introduction

Rapid urbanisation in Dar es Salaam, the main commercial hub in Tanzania, has resulted in congested health facilities, poor quality care, and unacceptably high facility-based maternal and perinatal mortality. Using a participatory approach, the Dar es Salaam regional government in partnership with a non-governmental organisation, Comprehensive Community Based Rehabilitation in Tanzania, implemented a complex, dynamic intervention to improve the quality of care and survival during pregnancy and childbirth. The intervention was rolled out in 22 public health facilities, accounting for 60% of the city’s facility births.

Methods

Multiple intervention components addressed gaps across the maternal and perinatal continuum of care (training, infrastructure, routine data quality strengthening and utilisation). Quality of care was measured with the Standards-Based Management and Recognition tool. Temporal trends from 2011 to 2019 in routinely collected, high-quality data on facility utilisation and facility-based maternal and perinatal mortality were analysed.

Results

Significant improvements were observed in the 22 health facilities: 41% decongestion in the three most overcrowded hospitals and comparable increase in use of lower level facilities, sixfold increase in quality of care, and overall reductions in facility-based maternal mortality ratio (47%) and stillbirth rate (19%).

Conclusions

This collaborative, multipartner, multilevel real-world implementation, led by the local government, leveraged structures in place to strengthen the urban health system and was sustained through a decade. As depicted in the theory of change, it is highly plausible that this complex intervention with the mediators and confounders contributed to improved distribution of workload, quality of maternity care and survival at birth.

Food intake and cardiometabolic risk factors in rural Uganda

BACKGROUND

Along with a nutritional transition in Sub-Saharan Africa, the prevalence of non-communicable diseases is increasing rapidly. We assess the association between food intake and cardiometabolic risk factors in a rural population in Uganda.

METHODS

The present study was based on data from a household-based case-control study of diabetic and non-diabetic households in Southwestern Uganda, 2012-2013. We analysed food intake in 359 individuals age ≥ 13 years from 87 households, using a household food frequency questionnaire, and measures of glycated haemoglobin (HbA1c), height and weight. We used multinomial logistic regression to model abnormal HbA1c (≥5.7%) and weight status (underweight, normal weight and overweight) as an outcome of total food intake and by nine food groups. Results were reported as odds ratios (OR) with 95% confidence intervals (CI). Models were adjusted for three nested sets of covariates.

RESULTS

The diet primarily consisted of staple food (cassava and plantain). High-Glycaemic Index staple food was the most consumed food group (median = 14 servings/week, p25-p75: 11-17). Milk, meat, fish and vegetables were the least consumed food groups (medians: 0-3 servings/week). Median intake of sugary food was 6 servings/week (p25-p75: 2-9). The OR of having abnormal HbA1c or being overweight increased with every weekly serving of food (1.02, 95% CI: 1.00-1.04 and 1.01 95% CI: 1.00-1.03, respectively). Of specific food groups, each weekly serving of meat increased the OR of being overweight with 33% (95% CI: 1.08-1.64), and fruit intake decreased the OR of abnormal HbA1c (0.94, 95% CI: 0.88-1.00), though this latter association was attenuated after adjustment for weight status, aerobic capacity, and socioeconomic status.

CONCLUSION

Diet was monotonous, mainly consisting of cassava and plantain, and increasing food intake was associated with abnormal HbA1c and overweight. To prevent non-communicable diseases a diet with higher intake of fish and vegetables, and less sugary food is recommended.

Does resilience moderate the effect of intimate partner violence on signs of depression among Tanzanian pregnant women: A cross-sectional study

INTRODUCTION

Exposure to intimate partner violence (IPV) has been found to be associated with a multitude of poor health and quality of life outcomes. Among the risks exacerbated by IPV is prenatal depression. Resilience is hypothesized to protect against psychopathology after exposure to a traumatic influence. The present study aims to investigate resilience as a moderator of the effect of exposure to IPV on prenatal depression among pregnant women in Moshi, Tanzania.

MATERIAL AND METHODS

In this cross-sectional study, nested within a larger longitudinal study, pregnant women receiving antenatal care were interviewed about exposure to IPV, signs of depression using the Edinburgh Postpartum Depression Scale, and resilience using the abbreviated Connor-Davidson Resilience Scale. Logistic regression was used to test the effect of the interaction term of resilience and exposure to IPV during pregnancy on the risk of high level of signs of depression.

RESULTS

In total, 1013 women completed all interviews, 300 women reported exposure to IPV, and 113 had high levels of signs of depression. Mean resilience score was 14.26 (SD 9.45). Exposure to IPV was correlated with signs of depression (adjusted odds ratio 6.49, 95% CI 3.75-11.24). Resilience was not correlated with signs of depression, nor was the interaction term of resilience and exposure to IPV.

CONCLUSIONS

The study did not find that resilience acted as a moderator of the effect of exposure to IPV during pregnancy on the risk of prenatal depression. The cross-sectional design of the study may not be well suited to investigate resilience, which could take time to manifest. The abbreviated Connor-Davidson Resilience Scale has not been validated in a Tanzanian setting, or in the Swahili version. Practitioners should take note that all women and families affected by IPV should be afforded relevant assistance from social services, law enforcement, healthcare practitioners, and other relevant services, regardless of their apparent level of resilience.

The Association Between Intimate Partner Violence and Signs of Depression During Pregnancy in Kilimanjaro Region, Northern Tanzania

Intimate partner violence (IPV) against pregnant women is common with severe health consequences to women and their babies. The aim of the present study is to measure the association between IPV and signs of depression among pregnant women attending antenatal care in a semi-urban setting in northern Tanzania. A cross-sectional study was conducted from March 1, 2014, to May 30, 2015, among pregnant women attending routine antenatal care in Moshi Municipality, Tanzania. During their third trimester, self-reported exposure to IPV was assessed using a validated structured questionnaire adopted from the World Health Organization's (WHO) Multi-Country Study on Women's Health and Domestic Violence. Signs of depression were assessed using Edinburg Postpartum Depression Scale. A total of 1,116 pregnant women were included in the analysis. A total number of 433 (38.8%) reported to be exposed to at least one type of violence during their pregnancy, and 128 (11.5%) presented with signs of depression. The most common type of violence experienced was emotional violence (30.7%), followed by sexual violence (19.0%) and physical violence (10.0%). Exposure to at least one type of violence was the strongest predictor for depression (adjusted odds ratio [AOR] = 5.06; 95% confidence interval [CI] = [3.25, 7.86]), followed by women who reported their primary source of emotional support was individuals not related to their family as compared with support obtained from their male partner/husband (AOR = 2.25; 95% CI = [1.26, 4.02]). Positive HIV/AIDS status (AOR = 2.27; 95% CI = [1.01, 5.14]) and previous history of depression (AOR = 1.62; 95% CI = [1.00, 2.64]). After adjusting for other predictors and types of violence, physical violence was the strongest predictor for signs of depression (AOR = 4.42; 95% CI = [2.65, 7.37]). Signs of depression were commonly observed among pregnant women and strongly associated with exposure to any type of IPV. The present findings indicate an urgent need for screening depression and IPV to mitigate the adverse health outcomes related to both IPV and depression during pregnancy.

Postnatal depressive symptoms display marked similarities across continents

BACKGROUND

Postnatal depressive symptoms measured by the Edinburgh Postnatal Depression Scale (EPDS) are reported to display measurement variance regarding factor structure and the frequency of specific depressive symptoms. However, postnatal depressive symptoms measured by EPDS have not been compared between women representing three continents.

METHODS

A cross-sectional study including birth cohort samples from Denmark, Vietnam and Tanzania. Women were included during pregnancy at routine care sites. Depressive symptoms were self-reported 40-90 days postpartum using the EPDS. Exploratory and confirmatory factor analyses and generalized additive regression models were performed.

RESULTS

A total of N = 4,516 participated in the study (Denmark N = 2,069, Vietnam N = 1,278, Tanzania N = 1,169). Factor analyses identified three factors (anhedonia, anxiety and depression) that were almost identical in the three study populations. The only variation between countries was that the item 'self-harm' loaded differently. Women from Tanzania and Denmark were more likely to have an EPDS total score above cut-off 12 (12.6% and 6.4%), compared to women from Vietnam (1.9%) (p<0.001). A low level of education was associated with significantly more depressive symptoms after adjusting for country (p<0.001).

LIMITATIONS

EPDS data was collected at a later time point in the Danish sample.

CONCLUSIONS

Postnatal depressive symptoms constitute a three-factor model across cultures including the factors anhedonia, anxiety and depression. The frequency of postnatal depressive symptoms differs between high-, medium-, and low-income countries. However, clinicians should bear in mind that low-educated women worldwide are more likely to experience postnatal depressive symptoms.

Emotional violence exerted by intimate partners and postnatal depressive symptoms among women in Vietnam: A prospective cohort study

BACKGROUND

Previous studies have shown a relation between intimate partner violence (IPV) and postpartum depression (PPD). However, these studies have primarily focused on physical and sexual violence as predictors for postpartum depression and little attention has been given to emotional violence (EV), despite emotional violence having been well reported as the most common type of violence experienced by women. This present study aimed to investigate the association between various types of emotional experience during life with present partner and postnatal depressive symptoms among women in Vietnam.

METHODS

A total of 1,274 pregnant women were recruited from 24 communities in the Dong Anh District, Hanoi, Vietnam. They were interviewed four times: (a) at enrolment (before week 24 of pregnancy); (b) at a gestational age of 30-34 weeks; (c) 24-48 hours after delivery; and (d) 4-12 weeks after delivery. Emotional violence and postnatal depressive symptoms were measured using a questionnaire developed by the World Health Organization (WHO) and the Edinburgh Postpartum Depression Scale (EPDS), respectively.

RESULTS

A total of 639 (50.4%) women experienced at least one type of emotional violence with their present partner, whereas 104 women (8.2%) experienced postnatal depressive symptoms. Women exposed to emotional violence were more likely to experience postnatal depressive symptoms (OR = 3.15; 95%CI: 1.17-8.51). Other statistically significant predictors of increased postnatal depressive symptoms included type of employment, lack of family support after delivery, lower level of education, husband's preference for a specific sex of child, presence of mental disorder, and depression during pregnancy.

CONCLUSIONS

Among Vietnamese women, there was a statistically significant association between exposure to emotional violence with their present partner and postpartum depression. The findings indicate an urgent need for screening for all acts of emotional violence as risk factors for postnatal depressive symptoms.

Postpartum depression and child growth in Tanzania: a cohort study

OBJECTIVE

To examine the association between postpartum depression and child growth in a Tanzanian birth cohort.

DESIGN

Prospective cohort study.

SETTING

Moshi, Tanzania.

POPULATION

Pregnant women over the age of 18 who sought antenatal care at two health clinics in Moshi, and the children they were pregnant with, were assessed for inclusion in this study.

METHODS

The women were interviewed twice during pregnancy and three times after birth, the final follow up taking place 2-3 years postpartum. Signs of postpartum depression were assessed approximately 40 days postpartum with the Edinburgh Postnatal Depression Scale.

MAIN OUTCOME MEASURES

Child growth was assessed with anthropometric measurements at 2-3 years of age and expressed as mean z-scores.

RESULTS

In all, 1128 mother-child pairs were followed throughout the duration of the study. In total, 12.2% of the mothers showed signs of postpartum depression. Adjusted mean height-for-age z-score (HAZ) was significantly lower at 2-3 years follow up for children of mothers with postpartum depression than for children of mothers without (difference in HAZ: -0.32, 95% CI-0.49 to -0.15). Adjusted mean weight-for-height z-score (WHZ) was significantly increased for the children exposed to postpartum depression (difference in WHZ: 0.21, 95% CI 0.02-0.40), whereas there was no significant difference in adjusted weight-for-age z-score (WAZ; difference in WAZ: -0.04, 95% CI -0.20 to 0.12).

CONCLUSIONS

We found that postpartum depressive symptoms predicted decreased linear height in children at 2-3 years of age and slightly increased weight-for-height.

TWEETABLE ABSTRACT

Postpartum depression in Tanzanian mothers is associated with impaired child growth at 2-3 years of age.

Antenatal depressive symptoms and adverse birth outcomes in Hanoi, Vietnam

BACKGROUND

Antenatal depression is a significant health problem in low and middle- income countries. Although the condition is associated with severe adverse consequences for the mother and newborn, it remains a neglected problem. The purpose of this study was to describe the association between antenatal depressive symptoms and preterm birth (PTB), low birth weight (LBW), and small for gestation age (SGA).

METHODS

The study was conducted in Dong Anh District, Hanoi, Vietnam, among pregnant women of less than 24 weeks of gestation. Information on socioeconomic characteristics and reproductive history was collected at enrollment and ADS and experiences of intimate partner violence were assessed at week 32. Birth outcomes were determined at delivery. Bivariate and logistic regression analyses were applied to assess the associations between ADS and PTB, LBW, and SGA.

RESULTS

ADS was significantly associated with an increased risk of PTB (crude OR = 2.4; 95%; CI: 1.01-5.4 and adjusted OR = 2.4; 95% CI: 1.1-5.2, respectively) and a significantly increased risk for giving birth to an LBW infant (crude OR = 3.1; 95% CI: 1.4-7.0 and adjusted OR = 3.5; 95% CI: 1.6-7.6, respectively). In contrast, ADS was not statistically associated with small for gestation age.

CONCLUSION

ADS is associated with an increased risk of PTB and LBW but not associated with SGA.

Total sitting time, leisure time physical activity and risk of hospitalization due to low back pain: The Danish Health Examination Survey cohort 2007–2008

Aims: This study aimed to test the hypotheses that a high total sitting time and vigorous physical activity in leisure time increase the risk of low back pain and herniated lumbar disc disease. Methods: A total of 76,438 adults answered questions regarding their total sitting time and physical activity during leisure time in the Danish Health Examination Survey 2007–2008. Information on low back pain diagnoses up to 10 September 2015 was obtained from The National Patient Register. The mean follow-up time was 7.4 years. Data were analysed using Cox regression analysis with adjustment for potential confounders. Multiple imputations were performed for missing values. Results: During the follow-up period, 1796 individuals were diagnosed with low back pain, of whom 479 were diagnosed with herniated lumbar disc disease. Total sitting time was not associated with low back pain or herniated lumbar disc disease. However, moderate or vigorous physical activity, as compared to light physical activity, was associated with increased risk of low back pain (HR = 1.16, 95% CI: 1.03–1.30 and HR = 1.45, 95% CI: 1.15–1.83). Moderate, but not vigorous physical activity was associated with increased risk of herniated lumbar disc disease. Conclusions: The results suggest that total sitting time is not associated with low back pain, but moderate and vigorous physical activity is associated with increased risk of low back pain compared with light physical activity.

Household and familial resemblance in risk factors for type 2 diabetes and related cardiometabolic diseases in rural Uganda: a cross-sectional community sample

OBJECTIVES

Prevention of type 2 diabetes (T2D) has been successfully established in randomised clinical trials. However, the best methods for the translation of this evidence into effective population-wide interventions remain unclear. To assess whether households could be a target for T2D prevention and screening, we investigated the resemblance of T2D risk factors at household level and by type of familial dyadic relationship in a rural Ugandan community.

METHODS

This cross-sectional household-based study included 437 individuals ≥13 years of age from 90 rural households in south-western Uganda. Resemblance in glycosylated haemoglobin (HbA1c), anthropometry, blood pressure, fitness status and sitting time were analysed using a general mixed model with random effects (by household or dyad) to calculate household intraclass correlation coefficients (ICCs) and dyadic regression coefficients. Logistic regression with household as a random effect was used to calculate the ORs for individuals having a condition or risk factor if another household member had the same condition.

RESULTS

The strongest degree of household member resemblances in T2D risk factors was seen in relation to fitness status (ICC=0.24), HbA1c (ICC=0.18) and systolic blood pressure (ICC=0.11). Regarding dyadic resemblance, the highest standardised regression coefficient was seen in fitness status for spouses (0.54, 95% CI 0.32 to 0.76), parent-offspring (0.41, 95% CI 0.28 0.54) and siblings (0.41, 95% CI 0.25 to 0.57). Overall, parent-offspring and sibling pairs were the dyads with strongest resemblance, followed by spouses.

CONCLUSIONS

The marked degree of resemblance in T2D risk factors at household level and between spouses, parent-offspring and sibling dyads suggest that shared behavioural and environmental factors may influence risk factor levels among cohabiting individuals, which point to the potential of the household setting for screening and prevention of T2D.

[Global differences in causes and diagnostics of cardio-metabolic diseases]

Cardio-metabolic diseases (CMDs) such as obesity, type 2 diabetes (T2D) and hypertension are now highly prevalent throughout low- and middle-income countries, even though half of the T2D cases cannot be explained by obesity. Non-obese T2D individuals may have been exposed to foetal programming and/or be genetically susceptible to abdominal obesity. There is evidence for ethnic-specific risks for cardiometabolic disease. This calls for expanding research collaboration with so-called South partners in order to qualify decision making on diagnosis and prevention of CMDs at global level.

Diabetes Treatment as "Homework": Consequences for Household Knowledge and Health Practices in Rural Uganda

BACKGROUND

Health professionals assign diabetes patients "homework" in that they give them instructions on how to manage diabetes, recognizing that most diabetes care takes place in the home setting. We studied how homework is practiced and whether knowledge and behavioral practices related to diabetes self-management diffuse from patients to their housemates.

METHOD

This mixed-methods study combined quantitative data from a household survey including 90 rural Ugandan households (50% had a member with type 2 diabetes [T2D]) with qualitative data from health facilities and interviews with 10 patients with T2D. Focus for data collection was knowledge and practices related to diabetes homework. A generalized mixed model was used to analyze quantitative data, while content analysis was used for qualitative data analysis.

RESULTS

Patients with T2D generally understood the diabetes homework assignments given by health professionals and carried out their homework with support from housemates. Although adherence to recommended diet was variable, housemates were likely to eat a healthier diet than if no patient with T2D lived in the household. Knowledge related to diabetes homework diffused from the patients to housemates and beyond to neighbors and family living elsewhere. Knowledge about primary prevention of T2D was almost absent among health staff, patients, and relatives.

CONCLUSIONS

Homework practices related to T2D improve diabetes-related knowledge and may facilitate healthy eating in nondiabetic housemates. These findings suggest that having a chronic disease in the household provides an opportunity to improve health in the entire household and address the lack of knowledge about prevention of T2D.

Assessing drivers of the IgG4 antibody reactivity to recombinant antigen Bm14 in Wuchereria bancrofti endemic populations in East Africa

A high proportion of the human population in lymphatic filariasis (LF) endemic areas is positive for filarial specific IgG4 antibodies, including many individuals without microfilariae (mf; circulating larvae in the human blood) or circulating filarial antigens (CFA; marker of adult worm infection). The antibodies are commonly regarded as markers of infection and/or exposure to filarial larvae, but a direct association between the antibodies and these indices has not been well documented. The present study assessed the role and relative effect of potential drivers of the human IgG4 antibody reactivity to the recombinant filarial antigen Bm14 in Wuchereria bancrofti endemic populations in East Africa. Sera collected during previous studies from 395 well characterized individuals with regard to age, sex, mf, CFA, household vector biting and household exposure to infective filarial larvae were tested for IgG4 antibodies to Bm14, and associations between antibody reactivity and the different variables were statistically analyzed. IgG4 reactivity to Bm14 was highly positively associated with CFA, and to a lesser extent with age. However, an expected association with household exposure to infective filarial larvae was not found. Bm14 antibody reactivity thus appeared mainly to reflect actual infection of individuals with adult filarial worms rather than ongoing exposure to transmission. The analyses moreover suggested that many of the CFA negative but Bm14 positive individuals had early or low level infections where antibodies had been induced but where CFA was not (yet?) measurable. Although the study indicated that IgG4 reactivity to Bm14 is a marker of filarial infection, assessment of this reactivity, especially in children, will still be useful for indirect monitoring of changes in transmission intensity, including break of transmission and post-elimination surveillance, in LF control.

Accessing diabetes care in rural Uganda: Economic and social resources

Non-communicable diseases including type 2 diabetes (T2D) are increasing rapidly in most Sub-Saharan African (SSA) countries like Uganda. Little attention has been given to how patients with T2D try to achieve treatment when the availability of public health care for their disease is limited, as is the case in most SSA countries. In this paper we focus on the landscape of availability of care and the therapeutic journeys of patients within that landscape. Based on fieldwork in south-western Uganda including 10 case studies, we explore the diabetes treatment options in the area and what it takes to access the available treatment. We analyse the resources patients need to use the available treatment options, and demonstrate that the patients' journeys to access and maintain treatment are facilitated by the knowledge and support of their therapy management groups. Patients access treatment more effectively, if they and their family have money, useful social relations, and knowledge, together with the capacity to communicate with health staff. Patients coming from households with high socio-economic status (SES) are more likely to have all of these resources, while for patients with low or medium SES, lack of economic resources increases the importance of connections within the health system.

A comparison of cardiometabolic risk factors in households in rural Uganda with and without a resident with type 2 diabetes, 2012-2013

INTRODUCTION

Few studies have examined the health consequences of living in a household with a person who has been diagnosed with type 2 diabetes (T2D). We assessed the association of sharing a household with a person with diagnosed T2D and risk factors for cardio-metabolic diseases in Uganda, a low-income country.

METHODS

Ninety households with 437 residents in southwestern Uganda were studied from December 2012 through March 2013. Forty-five of the households had a member with diagnosed T2D (hereafter "diabetic household"), and 45 households had no member with diagnosed T2D (hereafter "nondiabetic household"). We compared glycosylated hemoglobin (HbA1c), fasting plasma glucose (FPG), hypertension, anthropometry, aerobic capacity, physical activity, nutrition, smoking, and diabetes-related knowledge of people without diagnosed T2D living in diabetic and nondiabetic households.

RESULTS

People living in diabetic households had a significantly higher level of diabetes-related knowledge, lower levels of FPG (5.6 mmol/L vs 6.0 mmol/L), and fewer smoked (1.3% vs 12.9%) than residents of nondiabetic households. HbA1c was significantly lower in people aged 30 years or younger (5.2% vs 5.4%) and in males (5.2% vs 5.4%) living in diabetic households compared to residents of nondiabetic households. No differences were found between the 2 types of households in overweight and obesity, upper-arm fat area, intake of staple foods or cooking oil, or physical activity.

CONCLUSIONS

Sharing a household with a person with T2D may have unexpected benefits on the risk factor profile for cardio-metabolic diseases, probably because of improved health behaviors and a closer connection with the health care system. Thus, future studies should consider the household for interventions targeting primary and secondary prevention of T2D.

Primary Health Care: a strategic framework for the prevention and control of chronic non-communicable disease

In 2014, chronic, non-communicable diseases (NCDs) represent the leading causes of global mortality and disability. Government-level concern, and resulting policy changes, are manifesting. However, there continues to be a paucity of guiding frameworks for legislative measures. The surge of NCDs will require strong and effective governance responses, particularly in low and middle-income countries. Simultaneously following the 2008 World Health Report, there has recently been renewed interest in Primary Health Care (PHC) and its core principles. With this, has come strengthened support for revitalizing this approach, which aims for equitable and cost-effective population-health attainment. In this light and reflecting recent major global reports, declarations and events, we propose and critique a PHC approach to NCDs, highlighting PHC, with its core themes, as a valuable guiding framework for health promotion and policy addressing this group of diseases. Responsible Editors: Nawi Ng, Umeå University, Sweden and Julia Schröders, Umeå University, Sweden.

Potential barriers to healthcare in Malawi for under-five children with cough and fever: a national household survey

Failure to access healthcare is an important contributor to child mortality in many developing countries. In a national household survey in Malawi, we explored demographic and socioeconomic barriers to healthcare for childhood illnesses and assessed the direct and indirect costs of seeking care. Using a cluster-sample design, we selected 2,697 households and interviewed 1,669 caretakers. The main reason for households not being surveyed was the absence of a primary caretaker in the household. Among 2,077 children aged less than five years, 504 episodes of cough and fever during the previous two weeks were reported. A trained healthcare provider was visited for 48.0% of illness episodes. A multivariate regression model showed that children from the poorest households (p = 0.02) and children aged > 12 months (p = 0.02) were less likely to seek care when ill compared to those living in wealthier households and children of higher age-group respectively. Families from rural households spent more time travelling compared to urban households (68.9 vs 14.1 minutes; p < 0.001). In addition, visiting a trained healthcare provider was associated with longer travel time (p < 0.001) and higher direct costs (p < 0.001) compared to visiting an untrained provider. Thus, several barriers to accessing healthcare in Malawi for childhood illnesses exist. Continued efforts to reduce these barriers are needed to narrow the gap in the health and healthcare equity in Malawi.

Prevalence of malaria and use of malaria risk reduction measures among resettled pregnant women in South Sudan

BACKGROUND

The study assessed aspects of malaria infection, prevention and treatment in a population of resettled pregnant women in South Sudan.

METHODS

During April and May 2008, a cross-sectional study was carried out to estimate malaria prevalence and to assess the use of malaria risk reduction measures and their associations with selected background characteristics. Two hundred and twenty women were tested for malaria parasitaemia and questioned about their malaria prevention and treatment practices.

RESULTS

The results showed a prevalence of Plasmodium falciparum parasitaemia of 9.1%. No statistically significant associations were observed between selected background characteristics and malaria infection status. However, school attendance was significantly associated with insecticide-treated net ownership (OR = 6.52, 95% CI 2.37-17.94; p = 0.001) and access to malaria diagnosis and treatment (OR = 3.20, 95% CI 1.26-8.16; p = 0.015).

CONCLUSIONS

The results suggest that educational attainment need not be very advanced to affect practices of malaria prevention and treatment. Primary school attendance was a stronger predictor for use of malaria risk reduction measures than any of the other selected background characteristics. Educational attainment, information and communication about malaria prevention and control play a pivotal role in increasing and improving use of malaria risk reduction measures.

Exploring knowledge, attitudes and practices related to diabetes in Mongolia: a national population-based survey

BACKGROUND

Non-communicable diseases (NCDs) are now the leading causes of mortality in Mongolia, and diabetes, in particular, is a growing public health threat. Mongolia is a nation undergoing rapid and widespread epidemiological transition and urbanisation: a process that is expected to continue in coming decades and is likely to increase the diabetes burden. To better inform policy and public-health responses to the impact of the growth in NCDs, a national NCD Knowledge, Attitudes and Practices survey was implemented in Mongolia in 2010; a section of which focused on diabetes.

METHODS

This survey was a nationally-representative, household-based questionnaire conducted by field-workers. Households were selected using a multi-stage, cluster sampling technique, with one participant (aged 15-64) selected from each of the 3540 households. Questions explored demographic and administrative parameters, as well as knowledge attitudes and practices around NCDs and their risk factors.

RESULTS

This research suggests low levels of diabetes-related health knowledge in Mongolia. Up to fifty percent of Mongolian sub-populations, and one in five of the total population, had never heard the term diabetes prior to surveying. This research also highlights a high level of misunderstanding around the symptomatology and natural progression of diabetes; for example, one-third of Mongolians were unaware that the disease could be prevented through lifestyle changes. Further, this study suggests that a low proportion of Mongolians have received counseling or health education about diabetes, with lowest access to such services for the urban poor and least educated sub-populations.

CONCLUSIONS

This research suggests a low prevalence of diabetes-related health-knowledge among Mongolians. In this light, health-education should be part of any national strategy on diabetes.

Hypertension and hypertension-related disease in mongolia; findings of a national knowledge, attitudes and practices study

BACKGROUND

Mongolia has a high and increasing burden of hypertension and related disease, with cardiovascular diseases among the leading causes of death. Yet little is known about the knowledge, attitudes and practices of the Mongolian population with regards to blood pressure. With this in mind, a national Non-Communicable Diseases knowledge, attitudes and practices survey on blood pressure was implemented in late 2010. This paper reports on the findings of this research.

METHODS

Using a multi-stage, random cluster sampling method 3450 participant households were selected from across Mongolia. This survey was interviewer-administered and included demographic and socio-economic questions. Sample size was calculated using methods aligned with the World Health Organization STEPS surveys.

RESULTS

One fifth of participants reported having never heard the term 'blood pressure'. This absence of health knowledge was significantly higher in men, and particularly younger men. The majority of participants recognised high blood pressure to be a threat to health, with a higher level of risk awareness among urban individuals. Education level and older age were generally associated with a heightened knowledge and risk perception. Roughly seven in ten participants were aware of the relationship between salt and blood pressure. Exploring barriers to screening, participants rated a 'lack of perceived importance' as the main deterring factor among fellow Mongolians and overall, participants perceived medication and exercise as the only interventions to be moderately effective at preventing high blood pressure.

CONCLUSION

Rural populations; younger populations; men; and less educated populations, all with lower levels of knowledge and risk perception regarding hypertension, present those most vulnerable to it and the related health outcomes. This research intimates major health knowledge gaps in sub-populations within Mongolia, regarding health-risks related to hypertension.

Exploring knowledge, attitudes, and practices related to alcohol in Mongolia: a national population-based survey

Background

The leading cause of mortality in Mongolia is Non-Communicable Disease. Alcohol is recognised by the World Health Organization as one of the four major disease drivers and so, in order to better understand and triangulate recent national burden-of-disease surveys and to inform policy responses to alcohol consumption in Mongolia, a national Knowledge, Attitudes and Practices survey was conducted. Focusing on Non-Communicable Diseases and their risk factors, this publication explores the alcohol-related findings of this national survey.

Methods

A door-to-door, household-based questionnaire was conducted on 3450 people from across Mongolia. Participants were recruited using a multi-stage random cluster sampling technique, and eligibility was granted to permanent residents of households who were aged between 15 and 64 years. A nationally representative sample size was calculated, based on methodologies aligned with the WHO STEPwise approach to Surveillance.

Results

Approximately 50% of males and 30% of females were found to be current drinkers of alcohol. Moreover, nine in ten respondents agreed that heavy episodic drinking of alcohol is common among Mongolians, and the harms of daily alcohol consumption were generally perceived to be high. Indeed, 90% of respondents regarded daily alcohol consumption as either ‘harmful’ or ‘very harmful’. Interestingly, morning drinking, suggestive of problematic drinking, was highest in rural men and was associated with lower-levels of education and unemployment.

Conclusion

This research suggests that Mongolia faces an epidemiological challenge in addressing the burden of alcohol use and related problems. Males, rural populations and those aged 25-34 years exhibited the highest levels of risky drinking practices, while urban populations exhibit higher levels of general alcohol consumption. These findings suggest a focus and context for public health measures addressing alcohol-related harm in Mongolia.

Change in composition of the Anopheles gambiae complex and its possible implications for the transmission of malaria and lymphatic filariasis in north-eastern Tanzania

BACKGROUND

A dramatic decline in the incidence of malaria due to Plasmodium falciparum infection in coastal East Africa has recently been reported to be paralleled (or even preceded) by an equally dramatic decline in malaria vector density, despite absence of organized vector control. As part of investigations into possible causes for the change in vector population density, the present study analysed the Anopheles gambiae s.l. sibling species composition in north-eastern Tanzania.

METHODS

The study was in two parts. The first compared current species complex composition in freshly caught An. gambiae s.l. complex from three villages to the composition reported from previous studies carried out 2-4 decades ago in the same villages. The second took advantage of a sample of archived dried An. gambiae s.l. complex specimens collected regularly from a fourth study village since 2005. Both fresh and archived dried specimens were identified to sibling species of the An. gambiae s.l. complex by PCR. The same specimens were moreover examined for Plasmodium falciparum and Wuchereria bancrofti infection by PCR.

RESULTS

As in earlier studies, An. gambiae s.s., Anopheles merus and Anopheles arabiensis were identified as sibling species found in the area. However, both study parts indicated a marked change in sibling species composition over time. From being by far the most abundant in the past An. gambiae s.s. was now the most rare, whereas An. arabiensis had changed from being the most rare to the most common. P. falciparum infection was rarely detected in the examined specimens (and only in An. arabiensis) whereas W. bancrofti infection was prevalent and detected in all three sibling species.

CONCLUSION

The study indicates that a major shift in An. gambiae s.l. sibling species composition has taken place in the study area in recent years. Combined with the earlier reported decline in overall malaria vector density, the study suggests that this decline has been most marked for An. gambiae s.s., and least for An. arabiensis, leading to current predominance of the latter. Due to differences in biology and vectorial capacity of the An. gambiae s.l. complex the change in sibling species composition will have important implications for the epidemiology and control of malaria and lymphatic filariasis in the study area.

A 22 year follow-up study on lymphatic filariasis in Tanzania: analysis of immunological responsiveness in relation to long-term infection pattern

Seventy-one individuals who had been examined for Wuchereria bancrofti microfilaraemia in 1975, some of whom had been offered mass treatment with diethylcarbamazine (DEC) in subsequent years, were re-identified in 1996 and examined for microfilaraemia, circulating filarial antigenemia and cellular and humoral immunoresponsiveness to crude antigen homogenates prepared from Brugia pahangi parasite material. 85.9% of the study individuals had the same infection status in 1975 and 1996, suggesting strong predisposition to infection over extended periods of time. IL-4, IL-5 and IFNγ responses were associated with being infection negative in 1996 whereas IL-10 responses were associated with being infection positive. Similarly, specific IgG3 and IgE were strongly associated with being infection negative in 1996 whereas specific IgG4, and thus high IgG4/IgE ratios, were strongly associated with being infection positive. Intermediary levels of mainly IL-5, IFNγ and PBMC stimulation indices were observed for study individuals who changed from being infection positive in 1975 to infection negative in 1996, or vice versa, suggesting a transition in cellular immunoresponsiveness associated with changing infection status. The findings suggest that some people are more disposed to infection with bancroftian filariasis than others and that this is largely unaffected by treatment with DEC. The findings also suggest that specific cellular and antibody responses are more related to current than past infection status, and that IL-4, IL-5, IFNγ, specific IgG3 and IgE are associated with parasite clearance, whereas IL-10 and specific IgG4 are associated with parasite protection.

Is the current decline in malaria burden in sub-Saharan Africa due to a decrease in vector population?

Background

In sub-Saharan Africa (SSA), malaria caused by Plasmodium falciparum has historically been a major contributor to morbidity and mortality. Recent reports indicate a pronounced decline in infection and disease rates which are commonly ascribed to large-scale bed net programmes and improved case management. However, the decline has also occurred in areas with limited or no intervention. The present study assessed temporal changes in Anopheline populations in two highly malaria-endemic communities of NE Tanzania during the period 1998-2009.

Methods

Between 1998 and 2001 (1st period) and between 2003 and 2009 (2nd period), mosquitoes were collected weekly in 50 households using CDC light traps. Data on rainfall were obtained from the nearby climate station and were used to analyze the association between monthly rainfall and malaria mosquito populations.

Results

The average number of Anopheles gambiae and Anopheles funestus per trap decreased by 76.8% and 55.3%, respectively over the 1st period, and by 99.7% and 99.8% over the 2nd period. During the last year of sampling (2009), the use of 2368 traps produced a total of only 14 Anopheline mosquitoes. With the exception of the decline in An. gambiae during the 1st period, the results did not reveal any statistical association between mean trend in monthly rainfall and declining malaria vector populations.

Conclusion

A longitudinal decline in the density of malaria mosquito vectors was seen during both study periods despite the absence of organized vector control. Part of the decline could be associated with changes in the pattern of monthly rainfall, but other factors may also contribute to the dramatic downward trend. A similar decline in malaria vector densities could contribute to the decrease in levels of malaria infection reported from many parts of SSA.

Association between mannose-binding lectin polymorphisms and Wuchereria bancrofti infection in two communities in North-Eastern Tanzania

The association between selected mannose-binding lectin (MBL) genotype polymorphisms and Wuchereria bancrofti infection status was assessed among individuals whose infection status had been monitored for three decades. Blood samples were collected in 2006 and examined for polymorphisms in the mbl-2 gene and for W. bancrofti-specific circulating filarial antigen (CFA) status. Logistic regression analysis showed a significant association between MBL genotype and CFA status, with low-expression MBL genotype individuals being almost three times more likely to be CFA positive than high-expression MBL genotype individuals (odds ratio [OR] = 2.90). When individuals' filarial infection (microfilaria) status in 1975 was included in the analyses, the gain of new infections between the two examination points was almost 10 times higher among individuals with low than among those with high MBL expression genotype (OR = 9.51). The susceptibility to W. bancrofti infection thus appears to be significantly affected by the MBL expression genotype of the host.

Immunoepidemiology of Wuchereria bancrofti infection in two East African communities: antibodies to the microfilarial sheath and their role in regulating host microfilaraemia

The response pattern of specific antibodies to the microfilarial sheath (sheath-Ab) of the mosquito-borne filarial parasite Wuchereria bancrofti was investigated in individuals from two East African communities with different levels of endemicity. Individuals from both communities presented a strong inverse relationship between positivity for sheath-Ab and being positive for microfilariae (mf) and circulating filarial antigens (CFA). The prevalence of sheath-Ab positivity was highest in young individuals, but peaked at a younger age in the high (1-14 years) than the low (15-19 years) endemicity community. IgG1, IgG2, IgG3 and IgE intensities to a crude adult filarial worm antigen were higher, and IgG4 intensities were lower, in sheath-Ab positive than in sheath-Ab negative individuals, probably reflecting the infection status of individuals. From the study it appears that individuals become sheath-Ab positive before mf and/or CFA can be detected in the peripheral blood, and only after later disappearance of sheath-Ab from the circulation can CFA and mf be diagnosed. In light of the findings, possible roles of the distinct sheath-Ab in the host-parasite relationship are discussed, and a hypothesis is proposed which suggests that sheath-Ab play an important role in the regulation of host microfilaraemia.

Immunoepidemiology of Wuchereria bancrofti infection: parasite transmission intensity, filaria-specific antibodies, and host immunity in two East African communities

We compared the age profiles of infection and specific antibody intensities in two communities with different transmission levels in East Africa to examine the contribution of humoral responses to human immunity to the vector-borne helminth Wuchereria bancrofti. The worm intensities were higher and exhibited a nonlinear age pattern in a high-transmission community, Masaika, in contrast to the low but linearly increasing age infection profile observed for a low-transmission community, Kingwede. The mean levels of specific immunoglobulin G1 (IgG1), IgG2, IgG4, and IgE were also higher in Masaika, but intriguingly, the IgG3 response was higher in Kingwede. The age-antibody patterns differed in the two communities but in a manner apparently contrary to a role in acquired immunity when the data were assessed using simple correlation methods. By contrast, multivariate analyses showed that the antibody response to infection may be classified into three types and that two of these types, a IgG3-type response and a response measuring a trade-off in host production of IgG4 and IgG3 versus production of IgG1, IgG2, and IgE, had a negative effect on Wuchereria circulating antigen levels in a manner that supported a role for these responses in the generation of acquired immunity to infection. Mathematical modeling supported the conclusions drawn from empirical data analyses that variations in both transmission and worm intensity can explain community differences in the age profiles and impacts of these antibody response types. This study showed that parasite-specific antibody responses may be associated with the generation of acquired immunity to human filarial infection but in a form which is dependent on worm transmission intensity and interactions between immune components.

Bancroftian filariasis: house-to-house variation in the vectors and transmission -- and the relationship to human infection -- in an endemic community of coastal Tanzania

The house-to-house variation in Wuchereria bancrofti vector abundance and transmission intensity, and the relationship of these parameters to human infection, were investigated in an endemic community in coastal Tanzania. Vector mosquitoes were collected in light traps set up in 50 randomly selected households once weekly for 1 year. They were identified, dissected and checked for filarial larvae. Vector densities and transmission potentials varied markedly between households, both for all vectors combined and for the individual vector species (Anopheles gambiae s.1., An. funestus and Culex quinquefasciatus), even between households located close to each other. The variation in vector abundance was probably mainly attributable to differences in the distance to breeding sites, to specific household features likely to ease mosquito entry and hiding, and to the number of household inhabitants. Household annual biting rates (ABR) correlated positively with household annual transmission potentials (ATP), indicating that intense vector biting led to a high transmission intensity. Intriguingly, however, the human filarial-infection status (as indicated by microfilaraemia or circulating filarial antigenemia) did not differ significantly between households with relatively high and lower ABR or ATP. Possible reasons for this result include the long time required for W. bancrofti infection to establish in humans, human behaviour affecting exposure, the sharing of mosquito populations between households, and differential susceptibility of humans to infection. The marked heterogeneity in exposure between households, and the lack of immediate relationship between transmission and detectable human infection at household level, should be taken into account when considering the transmission pattern of lymphatic filariasis.

Global burden of disease--a race against time

Low-income communities will within the next decades undergo rapid changes. The burden of non-communicable diseases (NCDs), such as diabetes, cardio-vascular disease and cancer, will comprise an increasing proportion of the total disease burden. The results of projections indicate that the already constrained health systems will face a double burden of disease, in which HIV/AIDS and other common infectious diseases will co-exist with the new NCDs. In order for preventive measures directed towards NCD to be cost-effective, these have to be implemented within the next 10-20 years.

Global transition in health

"Tempora mutantur et nos in illis" King Lothar I remarked by year 900 AD. What exactly changed in us over time, i.e. how patterns of the epidemiological transition in populations locally and globally might appear, was described by Omran in 1971 [1]. The effect of transition on health and diseases in populations was demonstrated by Frenkl et al in 1991 [2]. And which major public health problems following each other, and why, was underscored by LaPorte in 1995 [3]. In 2000, leaders of the world society decided to identify a range of common goals, the Millennium Development Goals (MDG), to be reached by year 2015. Many of the MDG are directly or indirectly related with the major health problems, particularly those hitting the poorest: lack of clean drinking water, unhealthy environment, high maternal mortality due to lack of care for the pregnant, and lack of control of major communicable, often fatal diseases like child diseases, malaria, HIV/AIDS and tuberculosis. It is remarkable that the specific chronic diseases of major public health relevance are in fact not mentioned in the MDG, even if these diseases increasingly are hitting populations in low- and middle-income societies, i.e. developing countries. The world community seems to prioritize the diseases that are most visible, and most often linked with poverty, namely the infectious diseases mentioned above, which together kill about 17 million people annually, often in combination with malnutrition, and the 0.6 million deaths related to birth and pregnancy. With the exception of HIV/AIDS, which also hit richer societies, these diseases of poverty have been under-prioritized regarding research as well. However, at the turn of the Millennium, the burden of "Western" non-communicable diseases was increasing fast in developing countries. And by 2025, the burden of non-communicable diseases is expected to have doubled globally, with half of the burden on developing countries. Therefore it may be rewarding to look backwards upon the three stages of Omran's original thesis on epidemiological transition, to understand life and death forwards, in a world in fast transition, cf. the Danish philosopher Soeren Kirkegaard: "it is true what philosophy tells us, that life must be understood backwards, while not forgetting the second sentence, that it must be lived forwards".

[Global transition in health]

Global epidemiological transition reflected in changed patterns of death and diseases was first described by Omran; decreasing death and disease rates from infectious diseases, particularly in children and the young, are followed by decreased fertility rate and increased longevity, and by degenerative, and man-made diseases in ageing populations. Omran could not foresee the HIV/AIDS pandemic or the dramatic fall in longevity and fertility in, for example, Russia. But his model remains of value for health planners and politicians. We advocate for research in the interplay between diseases, populations and systems in a world in fast transition.

Filarial-specific antibody response in East African bancroftian filariasis: effects of host infection, clinical disease, and filarial endemicity

The effect of host infection, chronic clinical disease, and transmission intensity on the patterns of specific antibody responses in Bancroftian filariasis was assessed by analyzing specific IgG1, IgG2, IgG3, IgG4, and IgE profiles among adults from two communities with high and low Wuchereria bancrofti endemicity. In the high endemicity community, intensities of the measured antibodies were significantly associated with infection status. IgG1, IgG2, and IgE were negatively associated with microfilaria (MF) status, IgG3 was negatively associated with circulating filarial antigen (CFA) status, and IgG4 was positively associated with CFA status. None of the associations were significantly influenced by chronic lymphatic disease status. In contrast, IgG1, IgG2, and IgG4 responses were less vigorous in the low endemicity community and, except for IgG4, did not show any significant associations with MF or CFA status. The IgG3 responses were considerably more vigorous in the low endemicity community than in the high endemicity one. Only IgG4 responses exhibited a rather similar pattern in the two communities, being significantly positively associated with CFA status in both communities. The IgG4:IgE ratios were higher in infection-positive individuals than in infection-negative ones, and higher in the high endemicity community than in the low endemicity one. Overall, these results indicate that specific antibody responses in Bancroftian filariasis are more related to infection status than to chronic lymphatic disease status. They also suggest that community transmission intensity play a dominant but subtle role in shaping the observed response patterns.

The effect of eight half-yearly single-dose treatments with DEC on Wuchereria bancrofti circulating antigenaemia

The effect of eight half-yearly treatment rounds with diethylcarbamazine (DEC; 6mg/kg bodyweight) on Wuchereria bancrofti-specific circulating filarial antigen (CFA), a marker of adult worm infection, was followed in 79 individuals who were CFA-positive before start of treatment. Half of these were also microfilariae (mf)-positive. Microfilaraemia decreased rapidly after onset of treatment and became undetectable after four treatments. Circulating antigenaemia also decreased progressively, but at a much slower rate. After two, four and eight treatment rounds, the mean CFA intensity was reduced by 81, 94 and 98%, and the prevalence of CFA positivity was 85, 66 and 57%, compared with pre-treatment, respectively. CFA clearance rates were negatively related to pre-treatment CFA intensities, and were higher among pre-treatment mf-negative individuals than among pre-treatment mf-positive individuals. Even among patients who had pre-treatment CFA intensities above the upper measuring level (32000antigen units), and who continued to have intensities above this level after treatment, a decrease in post-treatment CFA intensities was obvious from a continuous decrease in ELISA optical density values. Repeated DEC therapy thus appears to have a slow but profound and persistent macrofilaricidal effect, which in the long run may be beneficial to populations undergoing DEC-based control interventions by reducing the probability of future morbidity development.

Bancroftian filariasis: patterns of vector abundance and transmission in two East African communities with different levels of endemicity

Intensive monitoring of Wuchereria bancrofti vector abundance and transmission intensity was carried out in two communities, one with high-level endemicity for bancroftian filariasis (Masaika, Tanzania) and the other with low-level (Kingwede, Kenya), on the East African coast. Mosquitoes were collected in light traps, from 50 randomly selected households in each community, once weekly for 1 year. They were identified, dissected and checked for parity and filarial larvae. Anopheles gambiae s. l., An. funestus and Culex quinquefasciatus transmitted W. bancrofti in the two communities but the importance of each of these taxa differed between the communities and by season. The overall vector densities and transmission intensities were significantly higher in Masaika than in Kingwede (the annual biting rate by 3.7 times and the annual transmission potential by 14.6 times), primarily because of differences in the available breeding sites for the vectors and in the vectorial capacity of the predominant vector species. A marked seasonal variation in vector abundance and transmission potential contributed to the complex transmission pattern in the communities. Generally, these indices were higher during and shortly after the rainy seasons than at other times of the year. Considerable differences in W. bancrofti transmission were thus observed between communities within a relatively small geographical area (mainly because of environmentally-determined differences in vector habitats), and these were reflected in the marked differences in infection level in the human populations. The variation in vector abundance, vector composition and transmission intensity in the two communities is discussed in respect to its cause, its effects, and its significance to those attempting to control bancroftian filariasis.

Long-term effect of three different strategies for mass diethylcarbamazine administration in bancroftian filariasis: follow-up at 10 years after treatment

The long-term effect of three different strategies for mass diethylcarbamazine (DEC) administration in bancroftian filariasis was assessed 10 years after start of treatment in three endemic communities in Tanzania. The strategies were the standard 12 day treatment (strategy I); a semi-annual single-dose treatment (strategy II); and a monthly low-dose treatment (strategy III). Treatment was given only during the first year. Following reductions immediately after treatment, overall community microfilaraemia levels were approaching pre-treatment levels in all three communities, 10 years later. In individuals who were microfilaria-positive and treated at baseline, the treatment had a long-term effect on microfilarial intensities, with geometric mean intensities being only 11%, 13% and 2% of pre-treatment levels 10 years later for strategies I, II and III, respectively. This suppressive effect was most pronounced for strategy III, which also cleared microfilaraemia and circulating filarial antigenaemia in a larger proportion of treated individuals than the other strategies. Most of the follow-up individuals who developed microfilaraemia between 2 and 10 years after start of treatment had also been microfilaraemic before treatment, suggesting that reappearance of microfilaraemia may be due to surviving female worms and/or that previously microfilaraemic individuals have a higher chance of reinfection than previously amicrofilaraemic individuals.

A 26-year follow-up of bancroftian filariasis in two communities in north-eastern Tanzania

The results of surveys, for human bancroftian filariasis, carried out in 1975 and 1991 in endemic communities in north-eastern Tanzania have already been reported. In 2001, all consenting individuals from two of these communities (Tawalani and Kwale) were re-surveyed, and many of the individuals examined in the earlier surveys were re-identified. The findings revealed an extraordinarily static pattern of infection and disease over the 26 years of follow-up. By 2001, despite brief interventions introduced after the first two surveys, the community prevalences and mean intensities of microfilaraemia had almost returned to pre-treatment levels. The majority of re-identified individuals who had been found microfilaraemic in 1975 and 1991 were also microfilaraemic in 2001. Being found microfilaraemic in the first survey was a highly significant risk factor for being found microfilaraemic in the subsequent surveys. These observations strongly indicate that re-infection with Wuchereria bancrofti commonly takes place, and that, compared with an individual who has never been infected, an individual who has been infected in the past has a much higher chance of acquiring a new, detectable infection. As most of the re-identified individuals who were amicrofilaraemic in 2001 but microfilaraemic in one or both of the earlier surveys were still positive for circulating filarial antigens in 2001, it seems that, once an infection has been acquired, the chance of ever becoming free of infection is small. No relationship between past microfilaraemia and the development of chronic filariasis was observed but the number of clinical cases seen in 2001, among the re-identified individuals, was low. The significance of these findings to our understanding of the natural history of W. bancrofti infection is discussed.

The effect of repeated half-yearly diethylcarbamazine mass treatment on Wuchereria bancrofti infection and transmission in two East African communities with different levels of endemicity

The effect of repeated half-yearly mass treatment with diethylcarbamazine (DEC, 6 mg/kg body weight) on infection and transmission of Wuchereria bancrofti was assessed and compared in communities with high and low endemicity in eastern Africa, with pretreatment microfilaria (mf) and circulating filarial antigen (CFA) prevalences of 29.4% and 53.2% in the high endemicity community and 3.1% and 18.7% in the low endemicity community, respectively. Human infection was monitored by repeated cross-sectional surveys, and transmission by weekly light trap collection of vector mosquitoes in selected houses in each community. Treatments resulted in a progressive decrease in microfilaremia and circulating antigenemia in both communities, with relative reductions being considerably higher for mf than for CFA. Among pretreatment mf-positive individuals, more than 60% were diagnosed as mf negative and mean mf intensities were reduced by 99% in both communities after two treatment rounds. In contrast, only moderate reductions were seen in circulating antigenemia among pretreatment CFA-positive individuals, with mean intensities still being 24-39% of pretreatment values after two treatment rounds. Among the pretreatment mf/CFA-positive individuals, clearance to a CFA-negative status was negligible. Complete CFA clearance was only observed among pretreatment CFA-positive but mf negative individuals who also had much lower initial mean CFA levels than the mf-positive individuals. After treatment, the intensity of transmission decreased in the high-endemicity community, but this appeared mainly to be a consequence of a drought-induced reduction in vector density rather than to reduced mf load in the human population, since the proportion of mosquitoes carrying infective larvae was not reduced. No change in transmission or mosquito infectivity was observed after treatment in the low-endemicity community. Implications of these observations for the control of Bancroftian filariasis are discussed.

Filaria dance sign and subclinical hydrocoele in two east African communities with bancroftian filariasis

During population-wide cross-sectional surveys for Wuchereria bancrofti microfilaremia, circulating antigenaemia, and clinical disease in a high and a low endemicity community in East Africa in 1998, a portable ultrasound scanner was used simultaneously to examine the scrotal tissue of the male populations (n = 422 and 328, respectively) for signs of adult worms. The overall microfilaria (mf) and circulating filarial antigen (CFA) prevalences in the scanned males were 30.8% and 53.6% in the high and 4.3% and 19.8% in the low endemicity community, respectively. During ultrasound examination, the filaria dance sign (FDS)--indicating the presence of live adult W. bancrofti worms--was observed in 16.1% and 6.7% of the males in these communities, respectively. This examination also revealed that subclinical hydrocoele (fluid accumulation in the scrotal sac, not detected during physical examination for clinical hydrocoele) was very common, affecting 25.3% and 15.5% of the examined males in the high and low endemicity community, respectively. Both of these ultrasonographic signs started to appear around the age of puberty and were most common in adults. In the high endemicity community, the prevalence and mean intensity of mf and CFA were considerably higher in FDS-positive than in FDS-negative adult males, whereas no obvious difference in these parameters was noted between adult males with and without subclinical or the combination of clinical and subclinical hydrocoele. Associations were less clear in the low endemicity community, probably because of the low number of infected individuals. The application of ultrasonography as a tool in bancroftian filariasis epidemiological field studies thus indicated that scrotal pathology may be much more common in endemic areas than hitherto reported.

Bancroftian filariasis infection, disease, and specific antibody response patterns in a high and a low endemicity community in East Africa

Bancroftian filariasis infection, disease and specific antibody response patterns in a high and a low endemicity community in East Africa were analyzed and compared to assess the relationship between these parameters and community transmission intensity. Overall prevalences of microfilaremia and circulating filarial antigenemia were 24.9% and 52.2% in the high and 2.7% and 16.5% in the low endemicity community, respectively. A positive history of acute attacks of adenolymphangitis was given by 12.2% and 7.1% of the populations, 4.0% and 0.9% of the adult (> or = 20 years old) individuals presented with limb lymphedema, and 25.3% and 5.3% of the adult males had hydrocele, in the high and the low endemicity community, respectively. Both infection and disease appeared earlier and reached much higher levels in the high than in the low endemicity community. The observed overall and age-specific infection and disease patterns in the two communities were in agreement with the view that these are primarily shaped by transmission intensity. No statistically significant relationships between infection status of fathers and mothers and that of their children were observed in any of the communities for either microfilaremia or for circulating filarial antigenemia. The overall levels (prevalence and geometric mean intensity) of filarial-specific IgG1, IgG2, IgG4, and IgE were significantly higher in the high endemicity community than in the low endemicity dommunity. Surprisingly, the opposite pattern was found for IgG3. Community transmission intensity thus appears to be an important determinant of observed inter-community variation in infection, disease, and host response patterns in Bancroftian filariasis.

Efficacy of DEC against Ascaris and hookworm infections in schoolchildren

Diethylcarbamazine (DEC) is an important drug for treatment and control of lymphatic filariasis. To assess its possible effect on Ascaris and hookworm infections, we conducted a double-blind two-armed study with children in Tanzania. Twenty six Ascaris-infected children were given a single dose of DEC (6 mg/kg body weight) and 25 were given a placebo. Twenty children in the treatment group and eighteen controls were also infected with hookworms. One month after treatment the geometric mean intensity (GMI) of Ascaris egg output was reduced by 60.2% in the treatment group; two children (7.7%) had stopped excreting Ascaris eggs, and some Ascaris worms were also expelled. In hookworm-infected children in the treatment group, the geometric mean intensity of hookworm egg output was reduced by 6.7% 1 month after treatment. Neither for Ascaris nor for hookworm, however, was the observed reduction in egg output at 1 month after treatment statistically significant. The treatment efficacy of a single dose of DEC (6 mg/kg) in these infections therefore was low.

Transmission intensity and the immunoepidemiology of bancroftian filariasis in East Africa

Previous attempts to determine the interactions between filariasis transmission intensity, infection and chronic disease have been limited by a lack of a theoretical framework that allows the explicit examination of mechanisms that may link these variables at the community level. Here, we show how deterministic mathematical models, in conjunction with analyses of standardized field data from communities with varying parasite transmission intensities, can provide a particularly powerful framework for investigating this topic. These models were based on adult worm population dynamics, worm initiated chronic disease and two major forms of acquired immunity (larval- versus adult-worm generated) explicitly linked to community transmission intensity as measured by the Annual Transmission Potential (ATP). They were then fitted to data from low, moderate and moderately high transmission communities from East Africa to determine the mechanistic relationships between transmission, infection and observed filarial morbidity. The results indicate a profound effect of transmission intensity on patent infection and chronic disease, and on the generation and impact of immunity on these variables. For infection, the analysis indicates that in areas of higher parasite transmission, community-specific microfilarial rates may increase proportionately with transmission intensity until moderated by the generation of herd immunity. This supports recent suggestions that acquired immunity in filariasis is transmission driven and may be significant only in areas of high transmission. In East Africa, this transmission threshold is likely to be higher than an ATP of at least 100. A new finding from the analysis of the disease data is that per capita worm pathogenicity could increase with transmission intensity such that the prevalences of both hydrocele and lymphoedema, even without immunopathological involvement, may increase disproportionately with transmission intensity. For lymphoedema, this rise may be further accelerated with the onset of immunopathology. An intriguing finding is that there may be at least two types of immunity operating in filariasis: one implicated in anti-infection immunity and generated by past experience of adult worms, the other involved in immune-mediated pathology and based on cumulative experience of infective larvae. If confirmed, these findings have important implications for the new global initiative to achieve control of this disease.

Wuchereria bancrofti in a community with seasonal transmission: stability of microfilaraemia, antigenaemia and filarial-specific antibody concentrations

The effect of seasonal transmission on microfilaraemia, antigenaemia and filarial-specific antibody levels in individuals infected with Wuchereria bancrofti was investigated in a follow-up study in an endemic community in north-eastern Tanzania. The subjects were 37 adult male residents who were found to be positive for circulating filarial antigen (CFA) at the beginning of the study (26 of whom were also found microfilaraemic with W. bancrofti at this time). Blood samples were collected from each subject in July 1998, January 1999 and July 1999, during the seasons when transmission intensity was high, low and high, respectively. The mean intensities of microfilaraemia and the mean concentrations of CFA were each slightly higher during the low-transmission season than during the two high-transmission seasons but the differences were not statistically significant (P > 0.05). Similarly, the mean levels of filarial-specific IgG1, IgG2, IgG3, IgG4 or IgE did not differ to a statistically significant degree between the three examination times. Microfilaraemias and the levels of CFA and filarial-specific antibodies all therefore appeared to be remarkably stable and largely unaffected by the seasonal variation in transmission. That no variation in the mean IgG4/IgE ratio was observed over the study period may indicate that the level of resistance to W. bancrofti infection in the study subjects was also unaffected by the transmission season.