Community participation in Aedes aegypti control: a sociological perspective on five years of research in the health area ''26 de Julio'', Havana, Cuba

OBJECTIVE

Effective dengue prevention and Aedes aegypti control is a priority for the Cuban health authorities. To enhance effectiveness, strategies oriented towards a more active involvement of communities in control activities are being tested. This paper presents a sociological perspective on a pilot project conducted in the health area ''26 de Julio'' (La Havana) in 1999-2004.

METHODS

Instrumental case study based on an exhaustive content analysis of project documents and on observations of a sociologist.

RESULTS

The context and the pilot project are systematically described and an analysis of the evolution of the underlying concept of community participation is provided. The pilot experience was a dynamic process influenced by self-reflection of the research team, feedback from research partners and changes in the epidemiological context (provoked by two dengue outbreaks during the study period). Community participation evolved from being just one component in Aedes aegypti control directed by the health staff into a learning and empowering process for the people. This change in the concept of participation was reflected in different aspects of the pilot project such as the learning and evaluation processes.

CONCLUSION

Empirical evidence from 5 years of research in the particular context of Cuba showed that moves towards community-based Aedes aegypti control are feasible. However, in order to be successful, community-based dengue prevention should be a social learning process, implying a transfer of power and responsibilities to local people. Actions undertaken must be oriented towards creating local capabilities, strengthening existing structures and organizations and promoting group work for learning participation from participation itself.

HLA-A, -B, -C, and -DRB1 allele frequencies in Cuban individuals with antecedents of dengue 2 disease: Advantages of the Cuban population for HLA studies of dengue virus infection

Dengue virus infection has emerged as one of the most important arthropod-borne diseases. In some dengue-infected individual, the disease progresses to its severe, life-threatening form, dengue hemorrhagic fever (DHF). Host genetic factors may be relevant and predispose some individuals to the severe dengue disease. The unique history of dengue outbreaks in Cuba is extremely advantageous for genetic studies of dengue disease resistance or susceptibility. Consequently, samples collected from 120 healthy individuals that developed dengue fever (DF) and DHF during the 1997 dengue 2 outbreak in the Santiago de Cuba municipality were HLA genotyped using polymerase chain reaction-sequence-specific primers. Polymorphism at the human leukocyte antigen (HLA) class I loci was significantly associated with DHF disease susceptibility, but polymorphism in the HLA-DRB1 was associated with protection. Amino acid peptides present in the poly-protein of the dengue 2 Jamaica strain, which are able to bind to the HLA class I and class II allotypes associated with susceptibility to or protection against the dengue clinical disease, respectively, were predicted using the BIMAS and SYFPEITHI predictive algorithms of peptide/MHC interaction.

Social and environmental determinants of Aedes aegypti infestation in Central Havana: results of a case-control study nested in an integrated dengue surveillance programme in Cuba

OBJECTIVE

To characterize the social and environmental risk factors associated with the presence of Aedes aegypti in order to improve community dengue control.

METHODS

A case-control study with 'cases' being households with entomologically confirmed A. aegypti infestation; personal interviews in Central Havana, a densely populated inner city area characterized by overcrowded housing and irregular water service. The participants were residents of 278 houses with infestation and 556 houses without infestation.

RESULTS

Greater risk of infestation was associated with lack of preventive measures, such as no larvicide in the water tanks (OR = 2.21) and use of flower vases for religious practice (1.93), not being economically active (1.64), vulnerable populations with higher risks in households with older people (1.52) and households with children (1.94).

CONCLUSIONS

Efforts to reduce infestations should continue to focus on water tank sanitation and improving housing conditions, but also engage community religious leaders to help promote safe practices. Vulnerable populations should be especially targeted by prevention activities. A surveillance programme can produce evidence to guide interventions.

[Dynamics of contracting HIV seen in its social, environmental and cultural dimension]

The adaptation of Coreil et al's communicable disease model to the dynamics of contracting HIV from the sensitive individual perspective was intended to be explained in this article. A literature review on the situation of this disease in Cuba and worldwide by developing the phylosophical debate on concepts and the basis for a different risk approach was made. The applicability and usefulness of this model for the study of determinants involved in HIV infection was shown.

[Diagnosis of Mycoplasma hominis, Ureaplasma parvum y Ureaplasma urealyticum in patients with bacterial vaginosis]

An observational descriptive study to determine the frequency of Mycoplasma hominis, Ureaplasma parvum and Ureaplasma urealyticum isolates in patients with bacterial vaginosis was carried out in 296 patients who had vaginal secretion and were seen at two hospitals. The diagnosis was based on Amsel's criteria. Endocervical swabs were taken from women positive to this disease for M. hominis and Ureaplasma spp. diagnosis by traditional methods. Polymerase chain reaction identified U. parvum and U. urealyticum. Bacterial vaginosis was diagnosed in 30.1% of females, and in 77.5% of them the studied urogenital mycoplasmas were present. M. hominis was the most common species (71%) whereas U. parvum and Urealyticum were detected in 23.2 % and 5.8% of cases respectively. The diagnosis of Mycoplasmas and ureaplasmas should be performed in females with bacterial vaginosis, which will allow applying adequate therapeutic control and avoiding future pathologies in the genital tract.

[Impact of highly active antiretroviral therapy in the clinical, immunological and virological response from AIDS patients]

A longitudinal prospective study was made to evaluate the clinical, immunological and virological response of a cohort of 34 AIDS patients in Cienfuegos provinces, who had been treated with highly active antiretroviral therapy (HAART). Males comprised 67.6% of the total number and average age was 32 years. Sexual infection path was identified in 91.2% of cases. The CD4+ T counting under 200 cells defined AIDS in 79.4% of individuals. Twenty six patients suffered minor opportunistic infections (76.5%) whereas 32.4% got sick due to some major opportunistic disease prior to the therapy. After this therapy, these frequencies lowered to 20.6% and 11.8% respectively. Average CD4+ counting at the starting of HAART was 196 cell/mm3 and exceeded 400 cells in the rest of further countings. From a PVC average of 15 251 copies/mL one year after therapy, this figure reduced to 8 048 copies at 2 years. Only 10 cases required hospitalization after a HAART (29.4%). Treatment adherence reached over 80% and was correlated to immunological restoration. Survival after one year was 100% and only 2 patients died in the following 4 years. The positive impact of HAART on the frequency of opportunistic infections, immunological restoration and survival was proved.

[Study of phenotypical and antimicrobial susceptibility markers in enteric Escherichia coli strains]

Forty strains of Escherichia coli isolated from children under 5 years of age with acute diarreas, coming from different provinces of the country , were analyzed. Four important phenotypical determinants were tested: sorbosa, sorbitol, enterohemolysin and 0157:H7 serology, in order to select those strains from enterohemorrhagic or Shiga toxin-producing category. Likewise, they were characterized by biotyping and antimicrobial susceptibility methods. The use of phenotypical tests showed six strains with presumptive characteristics, four of which were most likely to be Shiga toxin-producing strains. In antimicrobial susceptibility test, the strains showed high resistance mainly to ampicillin and trimethrophin-sulfamethoxasole. Another interesting finding were intermediate resistance and susceptibility values to augmentin, aztreonan and ceftriaxone. There were 12 antimicrobial resistance patterns of which 10 were multi-resistant.

[Clinical start of AIDS in Cuba]

Sixty three patients were studied using sociodemographic, behavioral, clinical-immunological and risk factor variables. The objective was to estimate the size of clinical start of AIDS in Cuba and characterize these patients in terms of potentially associated factors. Clinical start represented 4.2% of the total number of AIDS patients in Cuba. The risk of suffering the disease turned to be 17 times more frequent in over 50 years-old persons. Males represented 95.2%. The risk of dying was 3 times higher in those with clinical start of AIDS. The presentation form in 25% of patients was weakening caused by AIDS. Of the total number of patients, 34.9% stated that they had suffered some sexually transmitted infection prior to HIV diagnosis and almost half had had unprotected sexual intercourse with HIV-seropositive persons. Most of them (85.2%) were occasional. It was concluded that lack of knowledge on serological situation of patient constituted a barrier to treatment and survival. It was proved that we must insist on prevention and promotion campaigns in vulnerable groups and on active screening in the health area.

[Ecology of river mollusks of medical and veterinary importance in 3 sites in La Habana province]

An ecological research study was carried out in freshwater mollusk populations of medical and veterinary importance, in order to determine the biotic and abiotic factors that affect their dynamics. It was observed that the principal abiotic factors influencing abundance of mollusks were total hardness, salinity, acidity, alkalinity and CO2 concentration. Both aquatic plants and specific relations among mollusk groups were the principal biotic factors that affected the molluskan fauna. Species like Fossaria cubensis and Tarebia granifera appeared affected when the site diversity increased whereas the tiarid Melanoides tuberculata prevailed in almost all the ecosystems.

[Histoplasmosis with cutaneous manifestations in HIV/AIDS patients]

Cutaneous infection by histoplasmosis in Cuban HIV patients was researched. In a case series study, all HIV patients admitted to "Pedro Kouri" Institute from January 1st, 1992 to June 30th, 2003, who had been diagnosed with cutaneous histoplasmosis, were included. Of 44 patients with histoplasmosis, 52% (23 cases) developed the progressive disseminated form of histoplasmosis, which behaved as a subacute weakening disease. Young adults represented 56.5% and 82.6% were males mainly Caucasian (91.3%). Most of cases came from the Western provinces. Histoplasmosis was a marker disease in 39.1% of cases. CD4+ T-lymphocyte counting under 200 cell/mm3 was present in 78.9% of patients. Histoplasmosis seems to behave as an important marker disease for AIDs in seropositive patients. Serology was not the diagnosing method of choice for this cutaneous disease in AIDS patients.

Progress towards tuberculosis elimination in Cuba

SETTING

The Cuban National Tuberculosis Control Programme (NTCP) was implemented in 1962, and has included directly observed treatment since 1971 and DOTS since 1982.

OBJECTIVE

To assess the short-term trends of major indicators of tuberculosis (TB) elimination.

METHODS

A surveillance system has been created on treatment and case finding. Data from the National TB Registry of the Ministry of Public Health were reviewed.

RESULTS

The incidence of TB declined from 1965 to 1991 from 65.0 to 4.7 per 100000 population, then reversed in the period 1992-1994. The implementation of a re-intervention package recovered the increase from 1995 to 1998. From 1999 to 2003, 97.5% of TB suspects identified underwent sputum smear microscopy. The incidence rate declined from 10.0 to 7.2/100000. In 2003 the case detection rate was 92.2%; the overall TB cure rate was 92% and TB human immunodeficiency virus (HIV) co-infection was 3%. Two of Cuba's 15 provinces reached incidence rates of <5/100000, eliminating TB as a public health problem.

CONCLUSION

Low incidence, high detection and cure rates, along with low rates of TB-HIV co-infection, are evidence of progress towards the elimination of TB as a public health problem in Cuba, using DOTS in a context of good socio-cultural and technological interaction.

Genotypic resistance to antiretroviral drugs in patients infected with several HIV type 1 genetic forms in Cuba

The main objective of this study is to evaluate the prevalence of resistance-associated mutations to reverse transcriptase (RT) and protease (PR) inhibitors (I) 2 years after the introduction of antiretroviral treatment in Cuba, analyzing the mutations corresponding to different HIV-1 genetic forms circulating in Cuba. A total of 425 plasma samples were collected in 2003, corresponding to 175 (41.2%) subtype B and 250 (58.8%) non-B genetic forms, including 56 (22.4 %) non-B subtypes, 112 (44.8%) circulating recombinant forms (CRFs), and 82 (32.8%) unique RFs (URFs). Of these, 175 (41.2%) patients were under highly active antiretroviral therapy (HAART) and 250 (58.8%) were treatment-naive. The presence of RT and PR resistance-associated mutations was established by sequencing. Levels of resistance were evaluated according to the Stanford Database program (http://hivdb.stanford.edu). The prevalence of resistance to RTI was 52.2% among RTI-treated patients, 51.5% for subtype B, and 53.2% for non-B genetic forms, including CRF18_cpx, CRF19_cpx, subtype C, and BG URF. In treatment-naive patients it was 6.4% in subtype B and 4.2% in non-B subtypes and RFs. The prevalence of resistance to PRI was 30% among PRI-treated patients, 28% in subtype B and 31% in non-B genetic forms, and 3.2% among treatment-naive subjects, mostly BG recombinants. In conclusion, significant differences in the prevalence of resistance to RTI and PRI were not detected among the most frequent genetic forms from treated patients, suggesting that the genetic diversity of HIV-1 in Cuba does not play a main role in the development of resistance to antiretroviral drugs. The presence of transmitted resistance mutations supports the study of resistance at baseline of treatment.

Tuberculosis en niños de 0-14 años: Cuba, 1994-2003

INTRODUCTION

Tuberculosis in infants and children is a sign of continuous transmission. The present article describes the distribution and the trend in incidence rates of new tuberculosis cases in 0-15-year-olds in Cuba.

METHODS

Incidence rates and their trend were estimated by provinces and age groups for the 1994-2003 period. Distribution and overall variation percentages, annual average rates, and rates and percentages according to classification were determined.

RESULTS

The incidence rate decreased from 0.76 x 10(5) in 1994 to 0.31 in 2003 (59.2% of the overall reduction and 6.6% of the annual average reduction). The highest rate (1.06 x 10(5)) was found in 1995 (26 cases). In almost all provinces, the incidence trend decreased, except in the City of Havana, Sancti Spíritus, Santiago de Cuba, and the Isle of Youth. Childhood tuberculosis was mainly pulmonary (69.6%). Among the affected population, the highest percentages were found in the groups aged 10-14 years (35.6%) and 1-4 years (35.2%).

CONCLUSIONS

Tuberculosis is infrequent and is extremely uncommon in infants. Notification is low throughout the country and the overall trend shows a steady decrease.

Limitations to contact tracing and phylogenetic analysis in establishing HIV type 1 transmission networks in Cuba

Sequence analysis can be used to evaluate transmission networks. We have used retrospective samples to examine two HIV-1 transmission networks established by contact tracing. Regions of the HIV-1 region representing segments of gag and env were amplified by RT-PCR from frozen plasma samples and the sequence of each PCR product was determined. Within one of the networks (composed of 38 subjects) we found only a subset of the tested sequence clusters was consistent with the reported epidemiological linkage. Of 15 presumed transmission events where sequence data were available, 9 could be rejected either by subtype mismatch or by phylogenetic tests. In the other network (composed of 89 subjects) we were able to assess sequences for 26 presumed transmission events, 18 of which were rejected based on subtype discordance. Long lags in time between the time of transmission and the time of sequence sampling (ranging from 2 to 18 years) may limit the sensitivity for the detection of sequence linkage. Also, superinfection and incomplete epidemiological information are other factors that will limit the concordance of phylogenetic reconstruction and reported epidemiological linkage.

A cohort analysis of type 1 diabetes mortality in Havana and Allegheny County, Pittsburgh, PA

OBJECTIVE

To examine the mortality of type 1 diabetes (T1D) in two countries with very different health care systems using two population-based registries of childhood-onset T1D one in Havana (HA), Cuba, and the other in Allegheny County (AC), USA.

RESEARCH DESIGN AND METHODS

Cases diagnosed with T1D between 1965 and 1980 in HA and between 1965 and 1979 in AC were included. Follow-up started with diagnosis in each individual and ended as of 1 January 1991, or with death. Life-table analyses were used to examine the mortality rates in both populations by duration of diabetes.

RESULTS

Cumulative mortality by January 1991 in HA (14% in males and females, respectively) was higher than in AC (7% in males and 9% in females) for both genders (males, p=0.0005; females, p=0.0491). Mortality rates were considerably higher in HA for both men and women than in AC however, among females confidence intervals overlapped. Overall mortality rate for Caucasians (AC) was significantly lower than that for African-Americans (AC) or Hispanics (HR). An analysis of causes of death showed a greater proportion of deaths attributed to nephropathy (48.6%) in HA while acute complications (36%) and infections (27%) were more frequent in AC.

CONCLUSIONS

This study shows a two-fold greater mortality among people with childhood-onset T1D in Havana, Cuba, than in Allegheny, USA. Different strategies may be needed to increase survival among those with type 1 diabetes in the USA and Cuba.

Prevalence and risk factors of intestinal parasites in Cuban children

OBJECTIVES

To determine the prevalence of intestinal parasite infections and their risk factors in children in urban and rural settings in two Cuban municipalities.

METHODS

A total of 1320 Cuban schoolchildren aged 4-14 were tested by stool examination for intestinal parasite infections and evaluated by parental questionnaire for a number of common environmental, sanitary, socioeconomic and behavioural risk factors. Multivariate regression was applied to examine the relationship between the respective parasite infections and the risk factors.

RESULTS

Prevalences of intestinal parasite infections were 58% in Fomento and 45% in San Juan y Martínez; for helminth infections, these were 18% and 24% and for protozoa infections, 50% and 29%, respectively. Helminth infections were associated with high parental education (maternal: OR 0.68, CI 0.50-0.93; paternal: OR 0.71, CI 0.52-0.96), absence of toilet (OR 1.57, CI 1.12-2.19), consumption of water from a well or river (OR 0.56, CI 0.41-0.77) and eating unpeeled/unwashed fruit (OR 1.37, CI 1.01-1.87); protozoa infections were only associated with high maternal education (OR 0.72, CI 0.57-0.91).

CONCLUSIONS

Paediatric intestinal parasite infections are still prevalent in certain areas in Cuba and associated with a number of common environmental, socioeconomic and sanitary risk factors.

The application of monoclonal antibody methodology as a tool for serotyping leptospira isolates in Cuba

By using the monoclonal antibodies methodology we have classified Cuban serovars of leptospires isolated from blood culture of confirmed leptospirosis patients. The serogroups Pomona and Canicola were the most predominant found in our study. Pomona, Mozdok and Canicola serovars were the most prevalent types in these serogroups. Our study has essentially presented a validation of a monoclonal antibody method for the serotyping of Cuban leptospire isolates.

[Risk factors of pupal infestation with community-based Aedes aegypti in a municipality of Havana City]

The risk factors of pupal infestation with community-based Aedes aegypti were identified in four areas of Playa municipality, located in the urban zone of Havana City The deposits with the highest positivity to the vector were the artificial ones and the low tanks. It was confirmed that 99.03% of the sites visited contained at least one deposit with water, and that 4 areas presented a very similar behaviour in ratio of tanks per site, since in all of them the water was supplied every other day. That is why the difference in the positivity was not due to factors related to the water supply. Of the positive deposits, 87.17% were located in backyards, and 91.3% of the positive low tanks had no cover, or were partially covered. It was found that in the positivity of the deposits to the dengue vector, only 8.7% were non-community dependent. If there had had an active participation of the community directed to cover the tanks, to change the water in the water troughs, and to clean the backyards, the pupal infestation due to Aedes aegypti would have drastically increased in the studied areas.

[Outbreak of human leptospirosis in Guantánamo Province]

A characterization of the epidemic occurred in Guantánamo province during October and November 2005, and as well as of the activities developed for its control was made. The existence of favourable factors was confirmed, and as a result from the 42nd statistical week on there was an increase in the number of medical attentions with clinical pictures and epidemiologic elements. 885 suspected cases were notified, 61 were microbiologically confirmed, accounting for a positivity of 69%. The municipalities with the highest risk were Niceto Pérez, Guantánamo city, and Manuel Tames. Some activities were immediately carried out, with the multisectorial and interdisciplinary support from different organizations, allowing the control of the situation in less than a month. The study of this outbreak showed that leptospirosis is still a health problem in Cuba, and that it is necessary to join efforts and resources to control it.

[Laboratory advances in serologic diagnosis and research of human leptospirosis in Cuba]

For the first time in Cuba the rapid serologic technologies available worldwide were evaluated for the screening and confirmation of human leptospirosis. As its clinical recognition is difficult, the fast etiological diagnosis is of vital importance. Sensitivity and specificity values higher than 90 % were obtained in the confirmatory systems, and of 85 % in the screening systems. Of the severe patients studied by these technologies 50 % were positive. 203 cases corresponding to 4 epidemic outbreaks were confirmed, as well as 12 sick persons vaccinated with vaxSPIRAL, which demonstrates the vaccine effectiveness (78.1%). We developed and applied a latex system for a rapid screening of leptospirosis (LeptoCuba), with an excellent sensitivity, specificity, reproducibility, and stability. The application of new technologies for the screening and fast confirmation of the disease allowed to increase the positivity and quality of the diagnosis from 2000 to 2006, strengthening the microbiological surveillance in the country.

[Microbiological confirmation of two emergent outbreaks of human leptospirosis in Cuba]

Clinical samples from 293 patients with suspicion of leptospirosis were studied for the microbiologic confirmation of these events, in October-December 2005, when there were 2 outbreaks in humans, in Cuba. Sera samples of patients in acute phase and during convalescence, as well as hemocultures performed before the beginning of the antibiotic therapy, were analyzed. Conventional techniques (passive hemagglutination test and serogroups hemagglutination), and advanced or fast diagnosis techniques (Lepto tek Dri-Dot, Lepto-Cuba, Latex-India, Lepto tek Lateral Flow) were used for serologic diagnosis. In outbreak 1, 26 % of the studied cases were confirmed by serological tests (22/84), and 25% (5/20) through hemocultures; whereas in outbreak 11, 48 of the 162 studied cases (30%) were serologically confirmed, and it was possible to obtain isolation of leptospires in 6 of the 27 processed cases (22%). The main serovariants found by serology were Canicola, Ballum, Icterohaemorrhagiae, and Pomona. The rapid diagnosis methods were useful screening tools in the most severe cases or at pediatric ages. The two epidemiologic events were caused by pathogenic leptospires infection, which contributed to the adoption of hygienic-sanitary measures in both provinces.

Towards active community participation in dengue vector control: results from action research in Santiago de Cuba, Cuba

Community participation is advocated as essential for attaining effective dengue prevention, but knowledge of how to foster this is limited. In Santiago de Cuba, multiple small task forces were created at the neighbourhood level that included all stakeholders in the control of Aedes aegypti. The task forces assessed the perceived needs and elaborated action plans to promote specific behavioural change and to reduce environmental risks through social communication strategies and intersectoral local government activities. We monitored five dimensions of the participation process and assessed behavioural and environmental results and entomological outcomes. Participation was weak to good. At the household level, uncovered water storage containers decreased from 49.3% to 2.6% between 2000 and 2002, and removing larvicide from them dropped from 45.5% to 1%. There was a reduction of 75% in the absolute number of positive containers and a significant decrease from 1.23% to 0.35% in the house index. Local task forces, in which the interests of householders as well as vector control workers are directly represented, can lead to effective government-community partnerships that resolve problems of mutual concern.

Oral health in Cuba

Cuba's health care system is neither well known nor understood in the United States, so the opportunity to gain insight and facts about the system is significant. A sponsored trip to the island by a group of oral health practitioners is reported in this article by one of the participants. It was revealed that Cuba has invested a high percentage of its national budget in developing a sophisticated primary care system. Oral health services, as reported, are planned, organized and effective.

[Phenotypic and molecular identification of extended-spectrum beta-lactamase (ESBL) TEM and SHV produced by clinical isolates Escherichia coli and Klebsiella spp. in hospitals]

Nosocomial infections caused by gram-negative bacilli which produce extended spectrum beta-lactamase (ESBL) are associated with the increase of morbidity and mortality in hospitals. The objective of this study was to evaluate the frequency of ESBL, specifically the TEM and SHV type, produced by Escherichia coli and Klebsiella spp. strains, and also to determine the antimicrobial susceptibility of these isolates in comparison with other antibiotic families. A total of 326 strains were collected between 2002-2004 from hospitals in Havana City. The susceptibility tests were carried out according to the NCCLS guides and they were confirmed as. ESBL producers by the double disk diffusion method. The molecular characterization of these enzymes was determined by polymerase chain reaction (PCR), using two sets of oligonucleotides to amplify genes encoding TEM and SHV type beta-lactamase. The ESBL phenotype was detected in 31 (10%) Escherichia coli isolates, 19 of these strains (61%) carried the blaTEM genes, 5 (16%) blaSHV genes, 4 (12%) strains carried both genes and 11 strains (35%) carried the non-ESBL blaTEM and blaSHV genes. In Klebsiella spp. the ESBL phenotype was detected in 10 (36 %) isolates, only one strain carried the blaTEM gene. The most active antimicrobials against Escherichia coli were ciprofloxacin (64.5%) and gentamicin (58.07%); in the case of Klebsiella spp. the same antimicrobials were the most active with similar susceptibility (70%) for both. The carbapenems still remain the most active antibiotics against Escherichia coli and Klebsiella spp. strains, which are ESBL producers. However, their use should be closely controlled.

Dengue hemorrhagic Fever caused by sequential dengue 1-3 virus infections over a long time interval: Havana epidemic, 2001-2002

A dengue epidemic caused by dengue virus 3 (DENV-3) occurred in Cuba in 2001-2002. It included cases of dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). We report neutralizing antibody studies on sera from 54 of 78 DHF/DSS patients that provide evidence of infections occurring in the sequence DENV-1 followed by DENV-3. No sera showed infection in the sequence DENV-2 followed by DENV-3. Some sera showed a pattern of infection in the sequence DENV-1 followed by DENV-2 and then DENV-3. However definitive categorization of a tertiary infection was not possible because of broadly reactive antibodies, which could have been raised by infections in the sequence DENV-1 then DENV-3.

Assessment of human health vulnerability to climate variability and change in Cuba

In this study we assessed the potential effects of climate variability and change on population health in Cuba. We describe the climate of Cuba as well as the patterns of climate-sensitive diseases of primary concern, particularly dengue fever. Analyses of the associations between climatic anomalies and disease patterns highlight current vulnerability to climate variability. We describe current adaptations, including the application of climate predictions to prevent disease outbreaks. Finally, we present the potential economic costs associated with future impacts due to climate change. The tools used in this study can be useful in the development of appropriate and effective adaptation options to address the increased climate variability associated with climate change.

Race: a risk factor for dengue hemorrhagic fever

Cuban DHF/DSS outbreaks have provided evidence of a reduced risk of people of Negroid race for DHF/DSS compared to those of Caucasoid race. These observations from Cuban dengue outbreaks have significant epidemiological interest, as the differences in susceptibility to DHF/DSS among racial groups in Cuba coincide with that reported in African and Black Caribbean populations. In this article, we review the literature on race as a risk factor for DHF/DSS and discuss recent results from ongoing studies. Taking into consideration the origins of contemporary Cuban inhabitants, we propose that the Cuban, Caribbean Black and African populations share a common gene pool that could explain, at least partially, the low incidence of dengue hemorrhagic fever in Cuba and Caribbean and African countries. The central role played by immunological mechanisms in the pathogenesis of DHF/DSS has led us to consider that the polymorphic genes associated with the immune response must be carefully considered among those human genes regulating dengue disease severity that might be distributed unequally in Blacks and Whites.

Application of the pupal/demographic-survey methodology in an area of Havana, Cuba, with low densities of Aedes aegypti (L.)

Between the April and December of 2004, an Aedes aegypti (L.) pupal/demographic survey was conducted in the Playa municipality of Havana. The aims were to identify the key types of container in the production of the adult mosquitoes (and so provide a basis for targeted control) and assess transmission risk in terms of the number of pupae/person. Pupal abundance, as measured in the survey, was compared with traditional Stegomyia indices. The immature stages of Ae. aegypti were only found in 70 of the 15,153 containers that were investigated and the pupae of this species were only seen in 52 of the containers. Ground-level water-storage tanks yielded 74.1% of all the pupae, with a further 19.0% found in miscellaneous small containers. The utility of the pupal/demographic-survey methodology in the evaluation of dengue risk in the study area, and other areas of Cuba with low densities of Ae. aegypti, is discussed.

Aedes aegypti larval indices and risk for dengue epidemics

Entomologic indices can identify areas at high risk for disease transmission.

We assessed in a case-control study the test-validity of Aedes larval indices for the 2000 Havana outbreak. "Cases" were blocks where a dengue fever patient lived during the outbreak. "Controls" were randomly sampled blocks. Before, during, and after the epidemic, we calculated Breteau index (BI) and house index at the area, neighborhood, and block level. We constructed receiver operating characteristic (ROC) curves to determine their performance as predictors of dengue transmission. We observed a pronounced effect of the level of measurement. The BI_max (maximum block BI in a radius of 100 m) at 2-month intervals had an area under the ROC curve of 71%. At a cutoff of 4.0, it significantly (odds ratio 6.00, p<0.05) predicted transmission with 78% sensitivity and 63% specificity. Analysis of BI at the local level, with human-defined boundaries, could be introduced in control programs to identify neighborhoods at high risk for dengue transmission.

Is B vitamins deficiency associated with prevalence of Alzheimer's disease in Cuban elderly?

Alzheimer's disease (AD), is a major public health problem among the elderly in industrialized countries and a growing problem in developing countries. In Cuba, 14,6% of the population is older than 60 years. The AD prevalence in Cuba lies between 5,13-7,14%. Several studies have shown the relationship between the low nutritional status of B vitamins, hyperhomocysteinaemia with loss of neuro-cognitive function and AD. In studies during the epidemic neuropathy that affected Cuba between 1992-1993, B vitamins deficiency and smoking habits were strongly associated with the epidemic. Some studies in healthy adults and elderly after this epidemic have shown a sub-clinical deficiency of some B vitamins and a high prevalence of infection by Helicobacter pylori. The possibility that B vitamin deficiencies could be an additional risk factor for the high prevalence of the AD in Cuba is discussed.

[HIV/AIDS in adolescence, Cuba, 1987 to April 2004: an epidemiological approach]

A descriptive study was carried out in Cuba to characterize the epidemiological behavior of HIV/AIDS in adolescence (10-19 years) from 1987(report to the first cases) to April 2004. The universe was made up of 593 diagnosed cases; absolute frequencies, percentages and incidence/detection rates per 1,000,000 adolescents were estimated. Three hundred and sixteen cases (53.3%) were asymptomatic and 277 developed AIDS; 148 died, 590 of these cases were sexually infested. The average incidence rates in the 1999-2003 period were higher in Havana city and the municipality Isle of Youth with 9.2 and 13.1% per 1000,000 adolescents respectively. At the closing of 2003, City of Havana, Villa Clara and Cienfuegos exhibited the highest detection rates for both sexes, from 10 to 23.5 cases per 1,000,000 adolescents. The main way of transmission was sexual. City of Havana showed the highest incidence and detection rates of the country accompanied by Isle of Youth municipality in the 1999-2003 period, and followed by Villa Clara and Cienfuegos provinces in detection rates up to 2003.

[Pulmonary tuberculosis in persons from 4 municipalities in the City of Havana and diagnosed at university hospitals]

A retrospective, descriptive and exploratory study on the frequency of tuberculosis diagnosis in patients from 4 municipalities of the City of Havana was undertaken. Of a total number of 195 TB-suspected cases, 25 showed enough evidence recorded in their medical histories and 10 of them were finally diagnosed with tuberculosis: 5 BAAR(+) and 5 BAAR(-). Delay in getting acid-fast bacilli test results was 3 days or less in 75% of cases, being two days the mean value. Clinic and X-rays were the main elements to support a possible tuberculosis diagnosis. Both general and respiratory symptoms such as cough and expectoration prevailed as a cause of admission of these tuberculosis-suspected individuals. It seems that there is an adequate control over diagnosis and treatment but not over data collection, although evidence of subdiagnosis or subnotification, or both were not found. Further detailed studies are required

[Antimicrobial susceptibility in Pseudomonas aeruginosa strains taken from patients with cystic fibrosis]

Ninety strains of Pseudomonas aeruginosa isolated from pediatric patients with cystic fibrosis and respiratory infections at "William Soler" pediatric hospital were studied in the period from February to August, 2001, as part of a joint research project of the two hospitals. In vitro susceptibility of these strains to 10 antimicrobials, that is, azlocylline, ceftazidime, cefotaxime, ceftriaxone, gentamicin, tetracycline, ciprofloxacine, ofloxacine, chloranphenicol and trimethroprim/sulfamet-hoxazole was studied by Kirby-Bauer disk diffusion. The reference strain was ATCC 27853. The research work results showed that antimicrobial susceptibility values were within the allowable limits. Increased resistance to chloranphenicol (87.03%) and trimethoprim/sulfametoxazole (92.28%) as well as high sensitivity to azlocylline (85%), ceftazidime (87.09%), gentamicyn (94.09%), ciprofloxacine (94.8%) and ofloxacine (92.5%) were observed.

[Candida dubliniensis: need for correct diagnosis]

A study of 115 strains, which had been isolated from vaginal smears and identified at the beginning as Candida albicans, was conducted to find out if there was Candida dubliniensis in Cuba. The growth of those isolates that due to their morphological characteristics were identifified as either C. albicans or C. dubliniensis was checked up at 42 degrees in Sabouraud agar. C. albicans was the predominant species (88.69%). For the first time in Cuba, 13 C. dubliniensis strains were presumptively identified. The achieved results are of great benefit because they will contribute to the conduction of epidemiological and resistance studies to antifungicidal products.

[Prevalence of potentially pathogenic bacteria in nasopharynx of healthy children attending a day care center in Havana City]

During the first six-month period of 2001, a descriptive cross-sectional study of carriage in healthy children attending a day-care center in Havana City was performed. The objective was to find out the prevalence of potentially pathogenic bacteria and its association with possible risk factors. The design took into account the international and domestic regulatory bioethical requirements. Swabs of posterior nasopharynx of 160 children were directly cultured in brain heart agar plus sheep blood and in brain heart agar plus NAD, hemine and bacitracin and incubated for 18-24 h. Resulting isolates were identified using conventional techniques and the API NH system. Male children aged 3-4 years were predominant. A high percentage of nasopharyngeal carriage was detected; Haemophilus was isolated in 92.50% of cases, being Haemophilus influenzae present in 54.72% of children. Other pathogens were Streptococcus pneumoniae, beta-hemolythic Streptococcus, Staphylococcus aureus and Moraxella catarrhalis. A statistically significant difference was observed when comparing S. pneumoniae carriage and non-carriage in less than 2 years-old children. The colonizing patterns of potentially pathogenic bacteria were disclosed in children attending a day care center in Havana City.

[Behaviour of HIV/AIDS-related lymphoma in Pedro Kouri Institute. 2004-2005]

A prospective and descriptive study of 20 patients infected with HIV and admitted to "Pedro Kouri" Institute of Tropical Disease after a diagnosis of lymphoma was conducted. They were all evaluated at the onset of diagnosis by a thorough medical record exam and supportive studies such as complete blood count, globular sedimentation speed, CD4+ count, lactic acid dehydrogenase, HIV viral load, cytology and biopsy. Of this number, 85% presented with CD4+ count under 350 cell/mm3 at the time of diagnosis; however, only 55% showed viral loads exceeding 50,000 copies/mL. The predominant histological subtype was large diffuse cells and the most frequent location was the extrapulmonary site in 70% of cases. It called our attention that high levels of lactic acid dehydrogenase and extrapulmonary location of tumors were related. Statistically significant association was found (p < 0.05) between immunosuppresion condition of the patients given by CD4+ count below 350 cell/mm3 and advanced staging of the tumoral disease (stages III and IV).

[Evaluation of quality control of baciloscopy in tuberculosis diagnosis in Cuba]

This study was aimed at evaluating the diag-nosis of tuberculosis in Provincial Hygiene and Epidemiological Centers of the country including special municipality Isle of Youth. The quality control was performed on 4 382 sputum smears from January to December 2004 following the Manual of procedures of the National Tuberculosis Control program. Good quality in Ziehl Neelsen extension and staining was seen in 4003 smears (91.35%). The overall agreement coefficient between the National Tuberculosis Reference Laboratory and the rest of the provincial laboratories was 99.79%. Sensitivity and specificity figures were over 99%. These results showed the quality of sputum smears microscopy diagnosis at provincial laboratories and the need of carrying out permanent supervision, monitoring and re-training of staff in acid-fast bacilli test in order to lay down the foundations for the introduction of blind rechecking methods and panel of sputum smears, aimed at improving the tuberculosis diagnosis quality in Cuba.

[Extrapulmonary tuberculosis at "Benéfico Jurídico" hospital in the 1999-2003 period]

A retrospective and descriptive study was conducted on patients diagnosed with extrapul-monary tuberculosis and discharged from "Benéfico Juridico" neumological hospital in the 1999-2003 period. The objective was to describe the perfor-mance of this disease. As a result, it was find out that of a total number of 353 diagnosed patients, 14% had extrapulmonary tuberculosis, 58% of these patients were in the 35-54 years age group, being the average age 39 years. The most frequent clinical manifestation was pleural (81%) followed by ganglionic tuberculosis (15%). Sixty one percent of cases were diagnosed based on clinical indications. Only 8% of patients were diagnosed by isolation of tuberculosis bacillus in a Lowestein-Jensen culture.

[Entomological-ecological characterization of positive cases and suspected cases of West Nile virus in Sancti Spiritus province, Cuba]

A descriptive study on Culicidae species present in the habitats of the first positive cases and suspected cases of being affected by West Nile virus in Cuba and the conditions of its main breeding sources was presented. The samplings were taken in a radius of 1000 meters from the houses of 2 positive cases and 19 suspected cases. Sixteen Culicidae species of which 6 are associated to the virus transmission in North America, mainly Culex quinquefasciatus Say, 1023 and Culex nigripalpus Theobald, 1901. Among the fundamental risk factors are the inadequate environmental condition of permanent breeding sites (pits. ditches and streams) as well as unprotected water tanks inside the house and in the perimeter of the house.

[Prevalence and risk factors of age-related memory disorder in a health district]

INTRODUCTION

Normal aging is characterised by alterations affecting the cognitive functions. In 1958 Kral coined the term 'benign senescent forgetfulness' to designate a memory disorder that is different from those that occur during normal aging. In 1986, a group of researchers at the National Institute of Mental Health and other centres proposed a novel neuropsychological entity called age-related memory disorder. The determination of the prevalence, progression and risk factors of this condition currently represents an important challenge for the scientific community.

AIMS

To establish the rate of prevalence and to identify some of the risk factors involved in age-related memory disorders.

SUBJECTS AND METHODS

The universe consisted of all the patients over 50 years of age from a health district (234 individuals); the diagnostic criteria were applied to the whole sample. In addition to the patients, a control group was also chosen in order to be able to establish a correlation with selected risk factors.

RESULTS AND CONCLUSIONS

The prevalence rate was found to be 39.7%, of which 38.7% were males and 40.4% were females. It was also observed that the impairment was greater as the patient's age and the length of the disease history increased. As far as risk factors are concerned, it was observed that smoking and psychosocial characteristics constitute predisposing factors, while this was not the case for arterial hypertension, a history of dementia and the satisfaction of basic needs.

Health in Cuba

The poorer countries of the world continue to struggle with an enormous health burden from diseases that we have long had the capacity to eliminate. Similarly, the health systems of some countries, rich and poor alike, are fragmented and inefficient, leaving many population groups underserved and often without health care access entirely. Cuba represents an important alternative example where modest infrastructure investments combined with a well-developed public health strategy have generated health status measures comparable with those of industrialized countries. Areas of success include control of infectious diseases, reduction in infant mortality, establishment of a research and biotechnology industry, and progress in control of chronic diseases, among others. If the Cuban experience were generalized to other poor and middle-income countries human health would be transformed. Given current political alignments, however, the major public health advances in Cuba, and the underlying strategy that has guided its health gains, have been systematically ignored. Scientists make claims to objectivity and empiricism that are often used to support an argument that they make unique contributions to social welfare. To justify those claims in the arena of international health, an open discussion should take place on the potential lessons to be learned from the Cuban experience.

HIV Type 1 molecular epidemiology in cuba: high genetic diversity, frequent mosaicism, and recent expansion of BG intersubtype recombinant forms

Highly diverse HIV-1 genetic forms are circulating in Cuba, including subtypes B and G and two recombinant forms of African origin (CRF18_cpx and CRF19_cpx). Here we phylogenetically analyze pol sequences from a large collection of recent samples from Cuba, corresponding to 425 individuals from all Cuban provinces, which represents approximately 12% of prevalent infections in the country. RNA from plasma was used to amplify a pol segment by reverse transcription-polymerase chain reaction; phylogenetic analyses were performed with neighbour-joining trees and bootscanning. The distribution of genetic forms was subtype B, 41.2%; CRF19_cpx, 18.4%; BG recombinants, 11.6%; CRF18_cpx, 7.1%; subtype C, 6.1%; subtype G, 3.8%; B/CRF18 recombinants, 2.6%; subtype H, 2.1%; B/CRF19 recombinants, 1.7%; and others, 5.4%. Seventy-five (17.6%) viruses were recombinant between genetic forms circulating in Cuba. In logistic regression analyses, adjusting by gender and region, subtype B was more prevalent (OR 5.0, 95% CI 2.0-12.3) and subtype G less prevalent (OR 0.1, 95% CI 0.0-0.5) among men who have sex with men (MSM) than among heterosexuals. Within the main genetic forms of Cuba there were phylogenetic subclusters, several of which correlated with risk exposure or region. BG recombinants formed three phylogenetically related subclusters, corresponding to three different mosaic structures; most of these recombinants were from MSM from Havana City, among whom they have expanded recently, reaching 31% HIV-1 infections diagnosed in 2003. This study confirms the high HIV-1 diversity and frequent recombination in Cuba and reveals the recent expansion of diverse related BG recombinant forms in this country.

West Nile Virus infection in humans and horses, Cuba

A surveillance system to detect West Nile virus (WNV) was established in Cuba in 2002. WNV infection was confirmed by serologic assays in 4 asymptomatic horses and 3 humans with encephalitis in 2003 and 2004. These results are the first reported evidence of WNV activity in Cuba.

The state of the provision of nutritional care to hospitalized patients--results from The Elan-Cuba Study

Current nutritional care provision to 1905 patients hospitalized in 12 Cuban hospitals is presented in this article, diagnosed after conducting the Hospital Nutrition Survey (HNS), as part of the activities comprising the Cuban Study of Hospital Malnutrition (Elan-Cuba). The obtained HNS results were contrasted with standards regarding the nutritional assessment of hospitalized patient, the diagnosis of nutritional disorders occurring in the patient, and the identification of patients in need of nutritional intervention. The Elan-Cuba Study returned a 41.2% malnutrition rate [Barreto Penié J, Cuban Group for the Study of Hospital Malnutrition. State of malnutrition in Cuban hospitals. Nutrition 2005;21:487-97]. However, malnutrition was recorded as an independent diagnosis in only 0.4% of the surveyed clinical charts. It could not be shown that medical care teams were systematically applying any of the techniques and procedures recommended for the assessment of the nutritional status of hospitalized patients. In the best of the cases, only 40.6% of the surveyed patients had their height and weight recorded in their clinical charts at admission, 9.0% of those with more than 15 days of hospitalization had a prospective value of weight, and less than 20.0% of them had their serum albumin levels and/or their counts of Lymphocytes annotated on their clinical charts. Although 10.9% of the surveyed patients (median of the subcategories values; range: 3.5-41.2%) fulfilled an indication for nutritional intervention, support (enteral and/or parenteral) was only provided to less than 15.0% of them, with the exception made of patients on NPO, of whom 32.3% received either of the two modes of artificial nutrition listed above. It is to be noticed that none of the patients with chronic organic failure were on nutritional support at the time of the survey. The current nutritional care provision to the hospitalized patient might explain the increased rates of hospital malnutrition documented in the Elan-Cuba Study, and should lead to the design and urgent implementation of nutritional and metabolic intervention programs in the surveyed hospitals, given the deleterious effects of nutritional disorders upon the ultimate results of the medical and surgical actions, and the quality and costs of medical care.