A decade of vector control activities: Progress and limitations of Chagas disease prevention in a region of Guatemala with persistent Triatoma dimidiata infestation

INTRODUCTION

Chagas disease, a neglected tropical disease that affects millions of Latin Americans, has been effectively controlled in Guatemala after multiple rounds of indoor residual insecticide spraying (IRS). However, a few foci remain with persistent Triatoma dimidiata infestation. One such area is the municipality of Comapa, Department of Jutiapa, in the southeastern region of Guatemala, where control interventions appear less effective. We carried out three cross sectional entomological and serological surveys in Comapa to evaluate a decade of vector control activities. Baseline serological (1999) and entomological (2001-2) surveys were followed by three rounds of insecticide applications (2003-2005) and intermittent focal spraying of infested houses, until approximately 2012. Household inspections to determine entomological indices and construction materials were conducted in 2001, 2007 and 2011. Seroprevalence surveys were conducted in school-age children in 1999, 2007 and 2015, and in women of child bearing age (15-44 years) only in 2015. After multiple rounds of indoor residual sprayings (IRS), the infestation index decreased significantly from 39% (2001-2) to 27% (2011). Household construction materials alone predicted <10% of infested houses. Chagas seroprevalence in Comapa declined in school-aged children by 10-fold, from 10% (1999) to 1% (2015). However, seroprevalence in women of child bearing age remains >10%.

CONCLUSION

After a decade of vector control activities in Comapa, there is evidence of significantly reduced transmission. However, the continued risk for vector-borne and congenital transmission pose a threat to the 2022 Chagas disease elimination goal. Systematic integrated vector control and improved Chagas disease screening and treatment programs for congenital and vector-borne disease are needed to reach the elimination goal in regions with persistent vector infestation.

Social Interactions of Guatemalan Infants

The behavior of 52 rural Guatemalan infants of ages 8, 12, and 16 months was observed and recorded in their homes. Most interactions initiated by the caretaker seemed to consist largely of caretaking activities, and a relatively large verbal component was evident only with increasing age. Specific caretakers were associated with specific types of social interactions. The mother was the primary caretaker, being responsible for most of the carrying, questioning, ordering, teaching, and prohibiting of her son or daughter. Interactions initiated by the infant generally included touching and preverbal vocalizations. Most social play and touching involved siblings. Visual interest, vocalizing, and smiling were greatest when directed to a person outside the nuclear family. The father was found to have little effect on the social environment of the infants observed.

Traditionalism and Field Dependence

The relationship between preschool children's field dependence-independence and mothers' traditionalism and intellectual stimulation provided in the home was investigated in rural Guatemala. Contrary to several previous studies-which have not measured traditionalism at the level of the family, but rather compared children from more and less traditional communities-EFT scores were found to be unrelated to traditionalism. EFT scores were related to both material sources of stimulation as well as to the presence of better educated older siblings in the home. It was argued that in previous studies traditionalism has been confounded with other variables such as the availability of intellectual stimulation.

A Knowledge, Attitudes and Practices Survey Conducted Three Years after Halting Ivermectin Mass Treatment for Onchocerciasis in Guatemala

BACKGROUND

Mass drug administration (MDA) with ivermectin for onchocerciasis was provided in Guatemala's Central Endemic Zone (CEZ) over a 24 year period (1988-2011). Elimination of Onchocerca volvulus transmission was declared in 2015 after a three year post MDA surveillance period (2012-2014) showed no evidence of recrudescence. The purpose of the present study was to evaluate the knowledge, attitudes and practices (KAP) towards onchocerciasis and ivermectin among residents in the post endemic CEZ. A major interest in this study was to determine what community residents thought about the end of the ivermectin MDA program.

METHODOLOGY/PRINCIPAL FINDINGS

A total of 148 interviews were conducted in November 2014 in four formerly hyperendemic communities using a standard questionnaire on smart phones. The majority (69%) of respondents knew that the MDA program had ended because the disease was no longer present in their communities, but a slight majority (53%) was personally unsure that onchocerciasis had really been eliminated. Sixty-three percent wanted to continue to receive ivermectin because of this uncertainty, or because ivermectin is effective against intestinal worms. Eighty-nine percent of respondents said that they would seek medical attention immediately if a family member had symptoms of onchocerciasis (especially the presence of a nodule), which is a finding very important for ongoing surveillance.

CONCLUSIONS/SIGNIFICANCE

Many respondents wanted to continue receive ivermectin and more than half did not believe onchocerciasis had been eliminated. The ministry of health outreach services should be prepared to address ongoing concerns about onchocerciasis in the post endemic CEZ.

Culture and Dehydration: A Comparative Study of Caída de la Mollera (Fallen Fontanel) in Three Latino Populations

A sunken soft-spot or fontanel is a sign for dehydration in infants. Around the world, folk illnesses, such as caída de la mollera in some Latin American cultures, often incorporate this sign as a hallmark of illness, but may or may not incorporate re-hydration therapies in treatment strategies. This report describes a study of lay descriptions of causes, symptoms, and treatments for caída de la mollera in three diverse Latin American populations. A mixed-methods approach was used. Representative community-based samples were interviewed in rural Guatemala, Guadalajara, Mexico, and Edinburgh, Texas, with a 132 item questionnaire on the causes, susceptibility, symptoms, and therapies for caída de la mollera. Cultural consensus analysis was used to estimate community beliefs about caída. Interviews conducted in rural Guatemala (n = 60), urban Mexico (n = 62), and rural Texas on the Mexican border (n = 61) indicated consistency in thematic elements within and among these three diverse communities. The high degree of consistency in the illness explanatory models indicated shared beliefs about caída de la mollera in each of the communities and a core model shared across communities. However, an important aspect of the community beliefs was that rehydration therapies were not widely endorsed. The consistency in explanatory models in such diverse communities, as well as the high degree of recognition and experience with this illness, may facilitate communication between community members, and health care providers/public health intervention planners to increase use of rehydration therapies for caída de la mollera. Recommendations for culturally informed and respectful approaches to clinical communication are provided.

Exposure of seasonal migrant workers to Onchocerca volvulus on coffee plantations in Guatemala

Onchocerciasis (river blindness), which is close to being eliminated from Guatemala through semiannual administration of ivermectin, is still transmitted in one area of the country that coincidentally receives an annual influx of migrant workers to harvest coffee. Migrant workers generally are not included in semiannual ivermectin treatments, but if infected could serve as a reservoir. We report on two studies undertaken to measure the exposure to onchocerciasis (presence of IgG4 antibodies to a recombinant Onchocerca volvulus antigen, OV-16) among migrant workers. During two coffee harvest seasons, 170 migrant workers with a history of working in the disease-endemic area were tested and 1 (0.6%, 95% confidence interval = 0-3.2%) was seropositive. This low rate of exposure in migrant workers indicates that they are unlikely to play a significant role in transmission of onchocerciasis and may indicate that transmission in the last remaining disease-endemic area of Guatemala is decreasing significantly.

Population Biology of Pseudoperonospora humuli in Oregon and Washington

Pseudoperonospora humuli populations from Oregon and Washington were analyzed for genetic variation using random amplified polymorphic DNA (RAPD) and DNA amplification fingerprinting (DAF) markers. The genetic structure of the Oregon and Washington populations differed considerably. There was little genetic diversity in Washington, with only five RAPD and six DAF groups detected among 40 isolates tested. One genotype was predominant in Washing-ton. In contrast, 18 RAPD and 34 DAF groups were found among the 40 isolates tested from Oregon. No unique band profile associated with host cultivar was observed. It is suggested that the distinct difference in population structure between the two geographic regions might be due to climatic differences resulting in a higher frequency of sexual reproduction of P. humuli in Oregon than in Washington.

Women and war. What physicians should know

Most of today's 1.7 million women veterans obtain all or most of their medical care outside the VA health care system, where their veteran status is rarely recognized or acknowledged. Several aspects of women's military service have been associated with adverse psychologic and physical outcomes, and failure to assess women's veteran status, their deployment status, and military trauma history could delay identifying or treating such conditions. Yet few clinicians know of women's military history--or of military service's impact on women's subsequent health and well being. Because an individual's military service may be best understood within the historical context in which it occurred, we provide a focused historical overview of women's military contributions and their steady integration into the Armed Forces since the War for Independence. We then describe some of the medical and psychiatric conditions associated with military service.

A cross-cultural approach to the study of the folk illness nervios

To systematically study and document regional variations in descriptions of nervios, we undertook a multisite comparative study of the illness among Puerto Ricans, Mexicans, Mexican Americans, and Guatemalans. We also conducted a parallel study on susto (Weller et al. 2002, Culture, Medicine and Psychiatry 26(4): 449-472), which allows for a systematic comparison of these illnesses across sites. The focus of this paper is inter- and intracultural variations in descriptions in four Latino populations of the causes, symptoms, and treatments of nervios, as well as similarities and differences between nervios and susto in these same communities. We found agreement among all four samples on a core description of nervios, as well as some overlap in aspects of nervios and susto. However, nervios is a much broader illness, related more to continual stresses. In contrast, susto seems to be related to a single stressful event.

Seroprevalence of Trypanosoma cruzi infection among school-age children in the endemic area of Guatemala

In support of the National Program for Chagas Disease Control, we conducted a cross-sectional study to estimate the seroprevalence rate of Trypanosoma cruzi infection across the five Departments (Chiquimula, Jalapa, Zacapa, Jutiapa, and Santa Rosa) that are believed to comprise the entire principal endemic area in Guatemala. Also, so that the results could be used to identify areas of active transmission, we conducted the survey in school-aged children. We used an experimental enzyme-linked immunosorbent assay with blood samples obtained by finger prick to estimate the seroprevalence of T. cruzi. This assay has been previously tested and showed good sensitivity and specificity. Overall, the seropositivity rate for T. cruzi infection was 5.28% (235 of 4,450). Of 173 communities evaluated, 35 (20.23%) had a seropositive rate ranging from 10% to 45%. A number of parameters, including but not limited to living conditions, were examined for possible association with seropositivity. While there are several associations, the strongest association with seropositivity is living in a house with a thatch roof. The survey results will permit the Ministry of Health to stratify T. cruzi-endemic communities, enabling local health authorities to efficiently focus on vector control operations.

Regional variation in Latino descriptions of susto

Susto, a folk illness not recognized by biomedical practitioners as a disease, is now formally part of the diagnostic classification system in psychiatry as a "culture-bound syndrome." Susto has been reported among diverse groups of Latin Americans, but most of those reports are several decades old and many were conducted in Indian communities. This study focuses on contemporary descriptions of susto and uses a cross-cultural, comparative design to describe susto in three diverse Latino populations. Mestizo/ladino populations were interviewed in Guatemala, Mexico, and south Texas. An initial set of open-ended interviews was conducted with a sample of "key" informants at each site to obtain descriptive information about susto. A structured interview protocol was developed for use at all three sites, incorporating information from those initial interviews. A second set of structured interviews was then conducted with a representative sample at each site. Results indicate a good deal of consistency in reports of what susto is: what causes it, its symptoms, and how to treat it. There appear to be, however, some notable regional variations in treatments and a difference between past descriptions and contemporary reports of etiology.

Incidence and Spatial Distribution of Viruses in Hop Gardens of Washington State

The incidences of Hop latent virus (HpLV), Hop mosaic virus (HpMV), and American hop latent virus (AHLV), members of the genus Carlavirus, and Prunus necrotic ringspot virus and Apple mosaic virus, members of the genus Ilarvirus, were assessed for two hop cultivars, Horizon and Nugget, in Washington State. The spatial distribution of plants infected by the carlaviruses was assessed in two Horizon gardens in 2000 and one Nugget garden in 1993, 1994, and 1995. In the first Horizon garden (garden 1) and the Nugget garden, plants were separated by 2.1 m within and between rows. In these gardens, cultivation and the wide plant spacing discouraged contact between plants in either direction. In the second Horizon garden (garden 2), plants were separated by 4.3 m between rows and 1.0 m within rows. In all gardens, mechanical operations operated predominantly along rows; however, the closer plant spacing within rows in garden 2 permitted contact between adjacent plants within rows. In both Horizon gardens, the distribution of plants infected with HpMV was aggregated within rows. However, the distribution of plants infected with HpLV and AHLV was strongly influenced by contact between plants. In the Nugget garden, the distribution of plants infected by all three carlaviruses was autocorrelated within rows by 1995.

Cutaneous leishmaniasis in Guatemala: people's knowledge, concepts and practices

Ten rural communities in the northern area of Guatemala where cutaneous leishmaniasis (CL) is endemic were investigated to determine the residents' knowledge of the disease, their related concepts and practices, and their treatment preferences, and to identify the communication channels they use to acquire information. Of 425 heads of household interviewed, 96.7% could accurately describe a typical CL lesion. CL was found to be the fourth most frequently mentioned disease (in studies based on a free list format) and to be considered the sixth most serious (in studies based on paired comparisons). A series of three-way comparisons, used to analyse the subjects' concepts about the similarities of various discases, indicated that CL was considered to be most closely related to skin problems and to be different from any other group of diseases. All interviewees believed that it was necessary to receive treatment for CL, because without treatment the disease would progress, reach the bone, and take years to heal. More than half (55%) of the respondents knew about meglumine antimonate (Glucantime), the most commonly prescribed drug for treating CL in Guatemala. Only a few communication channels that were used by respondents to receive information were identified; the use of radio broadcasts and direct communication via the community leaders appeared to be the most effective.

The contrasting epidemiology of Cyclospora and Cryptosporidium among outpatients in Guatemala

We compared epidemiologic characteristics of Cryptosporidium and Cyclospora in surveillance data from outpatient departments in Guatemala. Routinely-submitted stool specimens were screened by microscopy. Age, sex, and symptom data were collected. Cyclospora was detected in 117 (2.1%) and Cryptosporidium in 67 (1.2%) of 5,520 specimens. The prevalence of Cyclospora peaked in the warmer months, while Cryptosporidium was most common in the rainy season. Both affected children more than adults, but Cryptosporidium affected children at a younger age than Cyclospora (median age 2 years versus 5 years; P < 0.001). Cyclospora showed a stronger association with diarrhea than Cryptosporidium, even when data were stratified by age. These contrasts may reflect differences in the relative importance of transmission modes, the frequency of exposure, and the development of immunity.

Exposure to diagnostic x-rays and incident age-related eye disease

OBJECTIVE

The purpose of this study was to evaluate whether a self-reported history of computed tomography or other x-rays of the head were associated with the incidence of age-related cataracts and maculopathy five years later.

METHOD

A 5-year longitudinal follow-up of the Beaver Dam Eye Study cohort (n=3,684, 43-86 years at baseline).

RESULTS

There was no evidence of a relationship between the x-ray exposures and the incidence of nuclear or cortical cataracts, or early maculopathy. There was a significant relationship to the incidence of posterior subcapsular cataract after adjusting for age only.

CONCLUSIONS

Adult patients in whom medical conditions warrant diagnostic x-rays of the head appear to be at little or no increased risk of age-related cataract or maculopathy. However, research efforts with more precise measures of x-ray exposure, longer follow-up, and further attempts to define uncontrolled confounders are warranted.

Incident cataract after a five-year interval and lifestyle factors: the Beaver Dam eye study

CONTEXT

A population-based study to investigate risk factors for age-related eye disease was begun in 1987 in a representative American community. Incidence of cataract was subsequently evaluated.

SPECIFIC OBJECTIVES

To examine the relationships of cigarette smoking, alcohol, and caffeine intakes to incidence of age-related cataracts five years later.

DESIGN

Observational epidemiologic incidence study of an adult population.

PARTICIPANTS AND INTERVENTION

Adults 43-84 years of age were identified during a census in 1987-1988, and examined at baseline (1988-1990) and after a five-year interval (1993-1995).

MAIN OUTCOME MEASURE

Standardized protocols were used at the baseline and follow-up evaluations for exposures and for objective identification of cataracts.

RESULTS

Cumulative incidence of nuclear cataract in right eyes was about 12%, cortical cataract about 8%, and posterior subcapsular cataract about 3%. In multivariable analyses of the general estimating equations type, there were significant associations between nuclear cataract and: pack-years smoked (odds ratio [OR] 1.05, 95% confidence interval [CI] 1.01, 1.09 per 10 pack-years); and current alcohol intake (OR 1.01, 95% CI 1.00, 1.02 per 10 grams ethanol/week). Cigarette smokers were more likely to have had cataract surgery in the interval between baseline and follow-up examinations.

CONCLUSIONS

Cigarette smoking and alcohol consumption were associated with modestly increased risks of incident nuclear cataract over a five-year interval.

Consensus theory model of AIDS/SIDA beliefs in four Latino populations

To describe Latino beliefs about AIDS (SIDA), Latino adults were sampled at two U.S. sites (Connecticut and Texas) and two international sites (Mexico and Guatemala). A 125-item questionnaire covered risk factors, symptoms, treatments, and sequellae of AIDS. The cultural consensus model was used to determine the cultural beliefs for each sample. Responses from 161 people indicated that a single set of beliefs was present at each site and that beliefs were shared across sites. Comparison of answers between samples indicated high agreement (p < .0007). The proportion of shared beliefs, however, decreased significantly between samples: .68 in Connecticut, .60 in Texas, .51 in Mexico, and .41 in Guatemala (p < .05). The proportion of positive answers similarly decreased from Connecticut to Guatemala (p < .001). Beliefs were stronger and more detailed in the higher prevalence areas. Furthermore, Latino beliefs tended to converge on biomedical beliefs about the disease.

Latino beliefs about diabetes

OBJECTIVE

To describe Latino beliefs about diabetes and assess heterogeneity in beliefs across different groups.

RESEARCH DESIGN AND METHODS

This study comprised a survey of 161 representative Latino adults from four diverse communities: Hartford, Connecticut; Edinburg, Texas; Guadalajara, Mexico; and rural Guatemala. A 130-item questionnaire covered causes symptoms, and treatments for diabetes. Information on demographics and acquaintanceship with someone with diabetes was also collected. The cultural consensus model was used to analyze the variation in responses to determine whether the degree of consistency within and between samples was sufficient to warrant aggregation and description as a single set of beliefs.

RESULTS

Homogeneous beliefs were present within each of the four samples. Although variability in responses increased significantly from Connecticut to Guatemala (P < 0.00005), there was significant agreement between samples on the answers (P < 0.0005). Answers tended to be concordant with the biomedical description of diabetes. Greater acculturation, higher educational attainment, and higher diabetes prevalence were associated with greater cultural knowledge about diabetes. In Connecticut, greater knowledge correlated with longer mainland U.S. residency (P < 0.05). In Mexico, those with average educational attainment knew more (P < 0.05). Finally, average knowledge levels were higher in communities with greater diabetes prevalence.

CONCLUSIONS

The cultural consensus model facilitated assessment of cultural beliefs regarding diabetes and diabetes management. Overall, Latino cultural beliefs about diabetes were concordant with the biomedical model. Variation in responses tended to characterize less knowledge or experience with diabetes and not different beliefs.

Epidemiologic studies of Cyclospora cayetanensis in Guatemala

In 1996 and 1997, cyclosporiasis outbreaks in North America were linked to eating Guatemalan raspberries. We conducted a study in health-care facilities and among raspberry farm workers, as well as a case-control study, to assess risk factors for the disease in Guatemala. From April 6, 1997, to March 19, 1998, 126 (2.3%) of 5, 552 surveillance specimens tested positive for Cyclospora; prevalence peaked in June (6.7%). Infection was most common among children 1.5 to 9 years old and among persons with gastroenteritis. Among 182 raspberry farm workers and family members monitored from April 6 to May 29, six had Cyclospora infection. In the case-control analysis, 62 (91%) of 68 persons with Cyclospora infection reported drinking untreated water in the 2 weeks before illness, compared with 88 (73%) of 120 controls (odds ratio [OR] 3.8, 95% confidence interval [CI] 1.4, 10.8 by univariate analysis). Other risk factors included water source, type of sewage drainage, ownership of chickens or other fowl, and contact with soil (among children younger than 2 years).

Predicting treatment-seeking behavior in Guatemala: a comparison of the health services research and decision-theoretic approaches

This study attempts to identify and describe factors associated with the choice of a health care source in rural Guatemala. Because of limited choice options, rural Guatemala makes an excellent location for studying the factors that affect utilization patterns. Illness case histories were collected from a random sample of 270 households in six villages. Then, two different methodological approaches were used to predict treatment actions. First, a sociobehavioral model, which encompasses enabling, predisposing, and need factors, was used to predict treatment choices. Using discriminant analysis we identified factors associated with the use of home remedies, a pharmacy, the health post, a physician, or folk healer. In a second, parallel study, descriptive interviews were used to identify important factors in choosing a treatment strategy. From these interviews, and from responses to hypothetical illness cases, we developed a decision model of treatment actions. Both models were tested against the set of illness cases. Results indicate that both approaches identify similar variables (especially, severity), although selection of variables through the multivariate analysis was much more successful in predicting treatment actions.

Data and information requirements for determining veterans' access to health care

The Department of Veterans Affairs (VA) is responding to changing requirements for decision-support data by maximizing the value of data contained in VA and non-VA sources. The data are used to answer questions relating to the accessibility and utilization of VA and non-VA health services. Access studies require accurate estimates of the number of persons served and the number of persons who could be served. To derive these population estimates, VA employs census data to develop projections of the veteran population at the national, state, and county levels. Data from many surveys are used to supplement the census data. Access studies also require quantitative and qualitative data on the characteristics of VA and non-VA health care delivery systems at the national, state, and local levels. The Department of Veterans Affairs obtains health care system data from external sources, including the US Department of Health and Human Services, the American Medical Association, and the American Hospital Association, and from internal sources, including VA surveys and the VA administration inpatient and outpatient files. Utilization studies need more detailed patient-level information than access studies. Data elements pertaining to the reason for health care encounters and the services rendered are obtained from survey data, the VA inpatient and outpatient administration files, the national Medicare database, and state Medicaid databases. The Department of Veterans Affairs'decision-support analyses for eligibility reform and health care system reform demonstrate the effectiveness of VA in analyzing data from many sources.

Knowledge, attitudes and practices during a community-level ivermectin distribution campaign in Guatemala

Community acceptance and participation are essential for the success of mass ivermectin chemotherapy programmes for onchocerciasis (river blindness). To explore the local understanding of the purpose of ivermectin and willingness to continue taking the drug, we performed questionnaire surveys in four communities with hyperendemic onchocerciasis after each of three ivermectin treatment rounds. More than 100 respondents participated in each KAP survey, representing the heads of 30% of the households in each community. The respondents rarely stated that the goal of the ivermectin treatment programme was to prevent visual loss. Instead, they said they were taking the drug for their general well-being, to cure the onchocercal nodule (filaria), or to cure the microfilaria, a term newly introduced by agents of the treatment programme. The principal reason identified for refusal to take ivermectin was anxiety about drug-related adverse reactions, and there were marked differences between communities in acceptance of treatment. In one community over 50% of residents initially refused to take ivermectin, although participation rates improved somewhat after programmatic adjustments. We recommend that ivermectin distribution programmes establish surveillance activities to detect where acceptance is poor, so that timely and community-specific adjustments may be devised to improve participation.

Knowledge, beliefs, and practices in relation to malaria transmission and vector control in Guatemala

As part of an effort to involve community members in malaria control activities, we studied knowledge, beliefs, and practices of residents of both the Pacific coastal plain and northeastern Guatemala related to malaria transmission and Anopheles albimanus control. Most residents recognized the role of mosquitoes in malaria transmission, but few knew how mosquitoes acquired their infections or understood the risk of having an untreated person in their midst. If this were more widely known, residents might put greater pressure on infected patients to seek timely and appropriate antimalarial treatment. Seventy-three percent of families owned one or more bed nets; however, even though most informants believed that bed nets help protect against malaria, the major reason for using them was to prevent nuisance mosquito bites. It is concluded that efforts should be made to promote bed net use by seeking ways to make them more affordable and by emphasizing their effectiveness as a barrier to nuisance mosquitoes. Although residents have a very positive opinion of the National Malaria Service spray teams, it is proposed that cooperation might be improved if malaria workers would emphasize the fact that house spraying reduces the numbers of nuisance mosquitoes and other pest insects, rather than focusing solely on malaria prevention, which most informants believed was less important. This study emphasizes the importance of understanding community beliefs and practices when planning or evaluating vector control activities.

Qualities of an ideal volunteer community malaria worker: a comparison of the opinions of community residents and national malaria service staff

Since the late 1950s, most malaria surveillance and treatment in rural areas of Latin America has been carried out by networks of unpaid community malaria workers, known as Volunteer Collaborators, who are selected and supervised by staff of the national malaria services (NMSs) in each country. In spite of the free and readily accessible antimalarial treatment available at these Volunteer Collaborator posts, many residents continue to seek treatment elsewhere and in most cases take doses of antimalarials that are insufficient to cure their infections. To identify ways in which the Volunteer Collaborator Network could be made more attractive to residents and to improve the process of selection of new workers, we asked community residents and Guatemalan NMS workers to rank order, according to their importance, 11 qualities or characteristics of an 'ideal' volunteer malaria worker. Community residents preferred someone who is available to take care of patients at all times of the day, is a responsible person, and has a general knowledge of medicine. No significant differences were noted in the rank orders of male and female residents or literate and illiterate residents. National Malaria Service workers also preferred someone who takes care of patients at all times of the day, even when busy. In addition, they wanted individuals who recognize the importance of their work as a Volunteer Collaborator, but choosing volunteers who had a general knowledge of medicine was not important. By modifying the procedures used to select Volunteer Collaborators so as to identify candidates with the qualities preferred by residents, it should be possible to increase acceptance and improve the performance of these volunteer workers.

Effects of permethrin-impregnated bed nets on malaria vectors of northern Guatemala

The authors evaluated the effects on malaria vectors of bed nets impregnated with permethrin over the course of a 16-month controlled study in four communities of Northern Guatemala. Anopheles albimanus and An. vestitipennis were the known malaria vectors in the area. Households were allocated to one of three experimental groups: those receiving bed nets impregnated with 500 mg/m2 of permethrin, those receiving untreated bed nets, and those where no intervention measures were taken. The impact of the treated and untreated bed nets on mosquito abundance, behavior, and mortality was determined by indoor/outdoor night-bite mosquito collections, morning pyrethrum spray collections, inspection of bed net surfaces for dead mosquitoes, and capture-release-recapture studies. The duration of the treated nets' residual insecticide effect was assessed by modified WHO cone field bioassays, and their pyrethrin content was estimated by gas-liquid chromatography analysis. The most important observation was that fewer mosquitoes were found to be resting in the households with treated bed nets. The treated nets probably functioned by both repelling and killing vector mosquitoes. Capture-release-recapture studies showed exit rates from houses with treated nets were higher (94%) than those from control houses (72%), a finding that suggests repellency. However, no significant differences were noted between the indoor night-bite mosquito collections at houses with and without treated nets. The horizontal surfaces of treated bed nets were nearly 20 times more likely to contain dead anopheline mosquitoes than were the comparable surfaces of untreated nets. the bioassays indicated that unwashed permethrin-impregnated bed nets retained their insecticidal activity for 6 months after treatment.

Community participation in malaria surveillance and treatment. III. An evaluation of modifications in the Volunteer Collaborator Network of Guatemala

In most rural areas of Latin America, malaria surveillance and treatment is carried out by a network of unpaid village malaria workers, known as Volunteer Collaborators, who are trained and supervised by the National Malaria Service. To identify ways in which the performance of these volunteer workers could be improved and to test changes that would make the Volunteer Collaborator Networks (VCNs) a more attractive model for community participation in malaria case detection and treatment in other regions, we tested a series of modifications in the VCN of Guatemala. These modifications included improved methods for selecting, supervising, and evaluating the volunteer workers and for collecting blood smears and reporting results, and the use of volunteer workers, known as Volunteer Medicators, who administered presumptive antimalarial therapy without taking a blood smear. A cost-effectiveness analysis of the modified VCN was also carried out. Two years after the modifications were introduced, Volunteer Collaborators identified nearly twice as high a percentage (33% versus 17%) of patients with suspected malaria in their villages. Delays in examining blood smears were reduced from 23 days to 11 days and delays from blood smear examination to curative treatment were reduced from 21 days to 7 days. The Volunteer Medicators identified and treated only a slightly higher percentage of patients than the Volunteer Collaborators (36% versus 33%). However, the cost of maintaining a network of Volunteer Medicators ($0.61 per patient treated) was much lower than the traditional VCN ($2.45) or the modified VCN ($1.85). Thus, with a few, simple and relatively inexpensive modifications, the efficiency and cost-effectiveness of Volunteer Collaborators can be markedly improved. Additionally, the VCN can be modified to make it a more suitable model for community-based malaria control and surveillance networks in other malarious areas of the world, which differ in terms of their level of endemicity, the goals of the malaria program, or the available health care infrastructure.

Permethrin-impregnated bed nets for malaria control in northern Guatemala: epidemiologic impact and community acceptance

Permethrin-impregnated bed nets were evaluated as a control measure for malaria in northern Guatemala. Twelve hundred forty participants were allocated to one of three experimental groups (impregnated bed nets [IBN], untreated bed nets [UBN], and controls) and followed up for a period of 13 months. The incidence density of malaria was significantly lower in both IBN (86 cases/1,000 person-years) and UBN groups (106/1,000) compared with that in controls (200/1,000). No difference in malaria incidence was noted between the IBN and UBN groups. Complaints of fever and chills were less frequent in the IBN group compared with controls. The participants were enthusiastic about the nets, which they saw as a means for avoiding nuisance insects more than for preventing malaria. Most (85%) wanted to wash their nets every 4-12 weeks, a practice known to shorten the duration of residual insecticide action. Larger studies are needed to determine whether or not impregnated bed nets offer an advantage over untreated nets in this setting.

Knowledge and Beliefs about Malaria on the Pacific Coastal Plain of Guatemala

Surveys of residents of the Pacific coast of Guatemala revealed a lack of knowledge and many misconceptions about the transmission and treatment of malaria, which could adversely affect malaria control measures and antimalarial therapy. Although mosquitoes are known to play an important role in malaria transmission and are thought to become infected by biting individuals with malaria, 75% of people interviewed believe that the mosquitoes can also acquire infections from contaminated water or by biting snakes and frogs. Furthermore, most residents believe that malaria can be acquired in other ways, such as by bathing too frequently or by drinking unboiled water. Although self-treatment of malaria with oral and injectable drugs purchased at stores and pharmacies is very common, less than 10% of the respondents were aware of the correct curative dose of chloroquine. Chloroquine injections are preferred to tablets and believed to be approximately three times as potent as tablets of the same concentration. Nearly two-thirds of the interviewees believed that pregnant and lactating women with malaria should avoid the use of chloroquine because it may cause a spontaneous abortion or dry up breast milk. Similar surveys of National Malaria Service workers and village malaria workers revealed higher levels of knowledge, although the village workers had many misconceptions about malaria transmission. An educational campaign directed at correcting some of these misconceptions should result in more appropriate self-treatment of malaria and greater acceptance by residents of personal protection methods and vector control and drug treatment programs.

Community participation in malaria surveillance and treatment. II. Evaluation of the volunteer collaborator Network of Guatemala

To evaluate the effectiveness of the Volunteer Collaborator Network (VCN) of Latin America as a community-based malaria case detection and treatment system, we conducted a study of the VCN of Guatemala. Volunteer Collaborators took 72.6% of all blood smears and identified 81.3% of all malaria cases reported by the Guatemalan National Malaria Service. The average volunteer treated 5.8 patients per month (range 0-32.8). In contrast, passive case detection (PCD) posts in government hospitals and health centers treated an average of 12.5 patients per month (range 0.5-91.4). The slide positivity rate of blood smears taken by Volunteer Collaborators was 16.2% compared with 9.7% for PCD posts in health centers and 10.3% for malaria workers during active case detection. The average delay between the date a blood smear was taken and examined ranged from 18.1 days on the Pacific coastal plain to 26.3 days in the less accessible northern region of the country. An additional 14.5 to 47.6 days elapsed before the radical treatments were initiated in these two regions. Seventy percent of the patients completed their radical treatments. In a survey conducted on the Pacific coastal plain of Guatemala, of 1,021 patients with chills and/or fever who believed they had malaria, 20.0% had visited a Volunteer Collaborator and 4.9% were treated at a government health center. Thus, the PCD network detected only 25% of all patients with symptoms suggestive of malaria. Most of the remaining patients treated themselves with antimalarial medications purchased in stores and pharmacies, but less than 15% of these patients used adequate courses of therapy. Furthermore, the rate of detection of symptomatic patients with malaria varied considerably from one community to another. Thus, data from the VCN are probably most useful when groups of communities or geographic areas are stratified for malaria control activities because at this level, variations between individual Volunteer Collaborator posts will be minimized. In spite of these problems, the VCN remains an excellent source of epidemiologic data for malaria control programs and the most practical means available for providing timely, appropriate antimalarial therapy to febrile patients in rural areas.

An epidemiological description of a folk illness: a study of empacho in Guatemala

Although anthropologists have provided descriptions of many folk illnesses, few have systematically evaluated their prevalence and determined who is at greatest risk for acquiring them. This report attempts to provide a systematic description of the folk illness empacho including the symptoms that define it. Illness prevalence was estimated and subpopulations at greatest risk were identified from illness histories collected from a random sample of households in rural Guatemala. Empacho was found to constitute a distinct cluster of symptoms: diarrhea, vomiting, headache, and lack of appetite. It differed from other gastrointestinal illnesses in that headaches were more likely and stomachaches were less likely to be reported. Empacho was highly prevalent and occurred in adults and children. Further, results showed that although empacho was frequently diagnosed by residents, folk healers were rarely consulted for any illness. Nevertheless, a strong association exists between a household diagnosis of empacho and the use of folk healers by those households (p less than .001).

Knowledge, attitudes and perceptions (KAP) of onchocerciasis: a survey among residents in an endemic area in Guatemala targeted for mass chemotherapy with ivermectin

If ivermectin distribution programs are to have maximum impact on the morbidity and transmission of human onchocerciasis there must be broad and sustained acceptance within the endemic communities. Educational activities, developed with careful consideration of community attitudes, should promote positive treatment seeking behavior while simultaneously addressing local reservations about the control effort. To better understand the ambient knowledge, attitudes, and practices concerning onchocerciasis in the context of ivermectin use in Guatemala, we conducted a survey among 145 heads of households in five endemic communities. Given the country's long-standing nodulectomy program, it was not surprising that 100% of persons interviewed had heard of the disease 'la filaria', which they defined as a skin nodule that could cause blindness. Ninety-five percent of respondents identified surgery as the only cure for the condition. Relatively few (39%) knew that la filaria was caused by a worm, although slightly more (50%) knew that the condition was acquired by the bite of an insect. The term microfilaria was not broadly recognized. We also determined that onchocerciasis was not perceived as a serious health problem: few persons (12%) mentioned la filaria when requested to provide a complete list of illnesses that occurred in the community, and the gravity of infection (based on rank ordering of common illnesses) was similar to that of a bad cold. Recommendations were made which might assist long-term acceptance of a national chemotherapy initiative against onchocerciasis in Guatemala.

Use of illiterate volunteer workers for malaria case detection and treatment

We evaluated the use of illiterate community volunteers for malaria case detection and treatment in Guatemala. Volunteer workers, known as Volunteer Medicators, were selected by members of their communities and were trained and supervised by National Malaria Service (NMS) staff. Their responsibilities included recording basic demographic data and administering a three-day course of chloroquine (25 mg kg-1) to all febrile patients who visited their homes. Patient information was recorded on a special form which consisted of stick-figure drawings. During a one-year evaluation period, no differences were noted between literate and illiterate Volunteer Medicators with respect to the length of time required for their training or supervision, the average number of patients they treated per month, the frequency of errors in recording data or administering medication, or their acceptance by the community residents.

Delivering bad news: the most challenging task in patient education

Communicating clinical findings that a patient's vision cannot be improved and/or will deteriorate is a challenging patient education responsibility. The bad news will be upsetting for the patient no matter how it is presented. By presenting findings in a thoughtful, step-by-step manner taking into account the patient's shock and distress and providing appropriate patient education information, the practitioner plays a critical role in facilitating the patient's participation in the rehabilitation process.

Du confirmation

The need for repeat antiglobulin testing to detect the Du phenotype in donor blood already labeled as Rh-negative was challenged. The confirmatory testing by hospital transfusion services rejected only 47 units in 2.6 million tested. The confirmatory antiglobulin test for Du currently required of hospital transfusion services could be omitted.

Heterogeneous growth and mental development of intrauterine growth-retarded infants during the first 3 years of life

Postnatal growth and development were studied in two groups of term infants with intrauterine growth retardation (IUGR) and one group of infants with normal birth weight up to 3 years of age (total sample, 205 infants). Infants with IUGR were classified as having low ponderal index (IUGR-LPI) or adequate ponderal index (IUGR-API). At birth, the two groups of infants with IUGR had similar birth weight, but length and head circumference measurements were significantly different. Overall, the IUGR-API infants remained lighter and shorter and had smaller head circumferences up to 30 months of age. The IUGR-LPI infants experienced catch-up growth in weight during the first months, because of greater fat deposition. At 24 months of age, the IUGR-API infants scored below the others on mental items. At 3 years of age the IUGR-API infants had the lowest values on seven of eight developmental measures and on the composite score; at these two time periods, the group with normal birth weight scored the highest, and the IUGR-LPI infants obtained intermediate values. It is concluded that infants with IUGR tend to follow postnatal growth and developmental patterns that are associated with their physical characteristics at birth.