Emergent Risk Group-4 (RG-4) Filoviruses: A paradox in progress

Filoviruses, categorized as World Health Organization (WHO) Risk Group 4 (RG-4) pathogens, represent significant global health risks due to their extraordinary virulence. The Filoviridae family encompasses Ebola strains such as Sudan, Zaire, Bundibugyo, Tai Forest (formerly known as Ivory Coast), Reston, and Bombali, in addition to the closely related Marburg and Ravn virus strains. Filoviruses originated from a common ancestor about 10,000 years ago and displayed remarkable consistency in genetic heterogeneity until the 20th century. However, they overcame a genetic bottleneck by mid-century. Paradoxically, this resulted in the emergence of boosted virulent strains from the 1970's onward. Filovirus research is included in the NIAID Biodefense Program and utilizes the highest level specialized protective laboratories, Biosafety Laboratory (BSL)-4. The spread of Filoviruses as well as other RG-4 pathogens within Africa poses a significant health threat increasingly both in Africa and out of Africa.

Decolonizing African history: Authenticité, cosmopolitanism and knowledge production in Zaire, 1971-1975

This article analyses the social and intellectual dynamisms of the Lubumbashi campus of the Université Nationale du Zaïre in the 1970s. It first highlights how Lubumbashi scholars participated in an early post-colonial attempt to radically transform the university's teaching, research and operations, at the crossroads of intellectual decolonization and cosmopolitanism. These efforts both overlapped and clashed with the official Zairian policy of Authenticité, a politically tinged reappraisal of the country's precolonial past. The article contributes to our limited knowledge of everyday life under Mobutu and of vernacular experiences of Authenticité, while highlighting Lubumbashi as an important node in the post-independence intellectual networks.

Natural History of Aerosol-Induced Ebola Virus Disease in Rhesus Macaques

Ebola virus disease (EVD) is a serious global health concern because case fatality rates are approximately 50% due to recent widespread outbreaks in Africa. Well-defined nonhuman primate (NHP) models for different routes of Ebola virus exposure are needed to test the efficacy of candidate countermeasures. In this natural history study, four rhesus macaques were challenged via aerosol with a target titer of 1000 plaque-forming units per milliliter of Ebola virus. The course of disease was split into the following stages for descriptive purposes: subclinical, clinical, and decompensated. During the subclinical stage, high levels of venous partial pressure of carbon dioxide led to respiratory acidemia in three of four of the NHPs, and all developed lymphopenia. During the clinical stage, all animals had fever, viremia, and respiratory alkalosis. The decompensatory stage involved coagulopathy, cytokine storm, and liver and renal injury. These events were followed by hypotension, elevated lactate, metabolic acidemia, shock and mortality similar to historic intramuscular challenge studies. Viral loads in the lungs of aerosol-exposed animals were not distinctly different compared to previous intramuscularly challenged studies. Differences in the aerosol model, compared to intramuscular model, include an extended subclinical stage, shortened clinical stage, and general decompensated stage. Therefore, the shortened timeframe for clinical detection of the aerosol-induced disease can impair timely therapeutic administration. In summary, this nonhuman primate model of aerosol-induced EVD characterizes early disease markers and additional details to enable countermeasure development.

Ebola Virus Dose Response Model for Aerosolized Exposures: Insights from Primate Data

This study develops dose-response models for Ebolavirus using previously published data sets from the open literature. Two such articles were identified in which three different species of nonhuman primates were challenged by aerosolized Ebolavirus in order to study pathology and clinical disease progression. Dose groups were combined and pooled across each study in order to facilitate modeling. The endpoint of each experiment was death. The exponential and exact beta-Poisson models were fit to the data using maximum likelihood estimation. The exact beta-Poisson was deemed the recommended model because it more closely approximated the probability of response at low doses though both models provided a good fit. Although transmission is generally considered to be dominated by person-to-person contact, aerosolization is a possible route of exposure. If possible, this route of exposure could be particularly concerning for persons in occupational roles managing contaminated liquid wastes from patients being treated for Ebola infection and the wastewater community responsible for disinfection. Therefore, this study produces a necessary mathematical relationship between exposure dose and risk of death for the inhalation route of exposure that can support quantitative microbial risk assessment aimed at informing risk mitigation strategies including personal protection policies against occupational exposures.

Comparison of Zaire ebolavirus realtime RT-PCRs targeting the nucleoprotein gene

In last five years, the Africa has faced two outbreaks of Zaire ebolavirus. These outbreaks have been the largest so far, and latest outbreak is still ongoing and affecting the Democratic Republic of the Congo. We tested in parallel three different Zaire ebolavirus (EBOV) realtime RT-PCRs targeting the nucleoprotein gene (EBOV NP-RT-qPCRs) described by Trombley et al. (2010); Huang et al. (2012) and Weidmann et al. (2004). These assays are used regularly in diagnostic laboratories. The limit of detection (LOD), intra-assay repeatability using different matrixes, sensitivity and specificity were determined. In addition, the primers and probes were aligned with the sequences available in ongoing and past outbreaks in order to check the mismatches. The specificity of all three EBOV NP-RT-qPCRs were excellent (100 %), and LODs were under or 10 copies per PCR reaction. Intra-assay repeatability was good in all assays, however the Ct-values were bit higher using the EDTA-blood based matrix. All of the primers and probes in EBOV NP-RT-qPCR assays have one or more mismatches in the probes and primers when the 2267 Zaire EBOV NP sequences, including strains Ituri from DRC outbreak (year 2018), was aligned. The EBOV strain of Bikoro (year 2018) circulating in DRC was 100 % match in Trombley and Weidmann assay, but had one mismatch in Huang assay.

Freshwater diatoms in the Democratic Republic of the Congo: a historical overview of the research and publications

An overview of the diatom research in the DR Congo is given based on literature data starting in 1938 with the work of Zanon and excluding the East African Lakes as these were already discussed in previous papers. For each literature record the diatom genera mentioned are presented as well as all diatom taxa described from the Congo as new. In total, 106 new taxa were documented, of which Nitzschia with 40 taxa is far the most important genus followed by Navicula s.l. and Pinnularia and with 15 and 13 taxa respectively. Particular attention was paid to the local research of students found in unpublished theses at bachelor, licentiate, master and PhD level. Diatom records in these works are almost all restricted to genus level, although in the last decade an attempt to delimit species can be observed. This accompanies the renewed taxonomic interest in the Congo basin during the last decade. Renewed taxonomic interest can also be seen in the genera: the first period being situated during the lumping period, while more recent works follow the current taxonomic classification, for example Navicula s.l. versus Navicula, Cavinula, Craticula, Diadesmis, Geissleria, Humidophila, Luticola, etc.

A novel Ebola virus antibody-dependent cell-mediated cytotoxicity (Ebola ADCC) assay

Ebolaviruses are highly virulent pathogens that cause Ebola viral disease (EVD). Data from non-human primate (NHP) models and from human survivors of EVD suggest that anti-Ebola antibodies play an integral role in protection. Antibody-dependent cell-mediated cytotoxicity (ADCC) is a potential mechanism through which anti-Ebola antibodies may mediate protection. We developed a robust Ebola-specific ADCC assay for use in ongoing trials of Ebola vaccines. Stable cell lines for inducible Zaire ebolavirus glycoprotein (EBOV GP) expression were developed to provide a uniform source of target cells in the assay, and were combined with an existing human natural killer (NK) cell line as the effector cell. When applied to commercially available anti-EBOV GP monoclonal antibodies, the assay clearly differentiated antibody with high ADCC activity from those with low or no ADCC activity. Anti-EBOV ADCC activity was also detected in plasma samples from rhesus macaques immunized with a candidate Ebola vaccine. The Ebola ADCC assay reported here will be a useful tool in studying the functionality of anti-EBOV GP antibodies elicited by Ebola vaccines in ongoing and future clinical trials.

Neutralizing the Threat: Pan-Ebolavirus Antibodies Close the Loop

The glycoprotein (GP) of ebolaviruses participates in a critical membrane fusion process to establish infection of a cell and therefore, represents an important target of both vaccines and antivirals. The latest reports on pan-ebolavirus monoclonal antibodies in small animal models may offer promising outcomes and insight into how best to target the GP in vaccine and antiviral discovery.

Evaluation of Medical Countermeasures Against Ebolaviruses in Nonhuman Primate Models

Several ebolavirus species, with varying lethality rates, have caused sporadic outbreaks in Africa resulting in human disease. Ebolaviruses also have the potential for use as biological weapons. Currently, there are no licensed vaccines or therapeutics to respond to outbreaks or deliberate misuse of ebolaviruses. Vaccine or therapeutic efficacy testing of medical countermeasures against ebolaviruses requires an animal model of disease; in vitro testing in cell culture cannot reproduce the complicated balance between host-pathogen interactions required for the ultimate licensure of a countermeasure. Depending on the target of the countermeasure, demonstration of efficacy in the nonhuman primate ebolavirus disease models will most likely be required before licensure. Here, we describe the selection and use of nonhuman primates for vaccine and therapeutic studies against ebolaviruses.

Pathology of experimental aerosol Zaire ebolavirus infection in rhesus macaques

There is limited knowledge of the pathogenesis of human ebolavirus infections and no reported human cases acquired by the aerosol route. There is a threat of ebolavirus as an aerosolized biological weapon, and this study evaluated the pathogenesis of aerosol infection in 18 rhesus macaques. Important and unique findings include early infection of the respiratory lymphoid tissues, early fibrin deposition in the splenic white pulp, and perivasculitis and vasculitis in superficial dermal blood vessels of haired skin with rash. Initial infection occurred in the respiratory lymphoid tissues, fibroblastic reticular cells, dendritic cells, alveolar macrophages, and blood monocytes. Virus spread to regional lymph nodes, where significant viral replication occurred. Virus secondarily infected many additional blood monocytes and spread from the respiratory tissues to multiple organs, including the liver and spleen. Viremia, increased temperature, lymphocytopenia, neutrophilia, thrombocytopenia, and increased alanine aminotransferase, aspartate aminotransferase, γ-glutamyl transpeptidase, total bilirubin, serum urea nitrogen, creatinine, and hypoalbuminemia were measurable mid to late infection. Infection progressed rapidly with whole-body destruction of lymphoid tissues, hepatic necrosis, vasculitis, hemorrhage, and extravascular fibrin accumulation. Hypothermia and thrombocytopenia were noted in late stages with the development of disseminated intravascular coagulation and shock. This study provides unprecedented insight into pathogenesis of human aerosol Zaire ebolavirus infection and suggests development of a medical countermeasure to aerosol infection will be a great challenge due to massive early infection of respiratory lymphoid tissues. Rhesus macaques may be used as a model of aerosol infection that will allow the development of lifesaving medical countermeasures under the Food and Drug Administration's animal rule.

[Land planning in Zaire through the spatial distribution of the population]

"Land planning in Zaire is examined through the analysis of population distribution by density and potential. The difference between these two techniques is that the calculation of population potential takes into account a genuinely geographical element, which is the distance between one given place and the other places within the area under consideration.... Taking potential as a criterion leads to developing an axis of communication from one end of the country to the other through densely populated, high-potential areas. Population density leads to a limited axis in each of the two regions with a high density of human occupation. In conclusion, the contribution of distance in land planning is to facilitate access for larger numbers of people and increase potential exchanges and contacts with other territories." (SUMMARY IN ENG)

Zaire. Departement de la Condition Feminine et de la Famille. Departmental Order No. 86-010, 5 July 1986

This order creates within the Department of Women's Condition and the Family a National Women's Documentation and Information Centre. The Centre has as its mission collecting facts on women and the family, analyzing them, interpreting them, and disseminating them. It is also charged with raising the awareness of women so that they can be led to participate in development.

Diarrheal epidemics among Rwandan refugees in 1994. Management and outcome in a field hospital

We describe the clinical course and outcome of Rwandan refugees with cholera-like illness (n = 567) and clinical dysentery (n = 1,062) treated at the Israeli Army field hospital in the disaster region of Goma, Zaire, during the summer of 1994. Vigorous fluid administration was the primary therapy, complemented with antibiotics for patients with presumed Shigella infection. Recovery rates were 94% and 96% for patients with cholera and dysentery, respectively. Mortality was substantially affected by comorbid conditions such as pneumonia and meningitis, which occurred in one-quarter of these patients. Infective, metabolic, and surgical complications (including three cases of intussusception) may have contributed to the deaths. The outcome of patients during diarrheal epidemics of cholera or bacillary dysentery may be favorable, even in disaster settings, if patients are evacuated promptly to medical facilities and appropriate therapy is instituted. We close with general observations on procedures to be followed in future epidemics of diarrheal diseases.

Maternal determinants of child survival in a rural African community

BACKGROUND

The aim was to determine maternal factors related to child survival in the rural area of Bwamanda, Northern Zaire.

METHODS

A prospective study of 30-months mortality was carried out in a cohort of 776 children aged 0-3 months, obtained by random cluster sampling. Inclusion criteria were exclusive breastfeeding, no severe prematurity and absence of severe protein-energy malnutrition, diarrhoea or acute respiratory infection. Mortality was recorded by regular home visits and inspection of hospital and funeral registers. Maternal factors that remain stable during follow-up were studied.

RESULTS

Factors associated with excess mortality in bivariate and multiple logistic regression analysis were: (i) mother has parity > 5 (relative risk [RR] = 1.5-4.2); (ii) distance from the health centre > 5 km (RR = 0.9-2.9); (iii) invaliding maternal diseases (RR = 1.2-9.0). Maternal school education (conditional odds ratio [OR] = 1.0-5.0) was significant in the multiple regression. In contrast to the other risk factors, mother-child separation or problems with breastfeeding were rare and did not significantly increase mortality.

CONCLUSIONS

Chronic stress situations created by maternal invalidity, high parity and distance from health care facilities, increase child mortality. Acute stress in the mother-child dyad seemed to be efficiently compensated for. In subsistence economy areas, maternal school education can be a disadvantage.

Prognostic indices for mortality of hospitalized children in central Africa

A hospital-based follow-up study was conducted between 1986 and 1988 at Lwiro (South Kivu Province, Zaire). Of 1,129 children in the study, three of four were severely malnourished, and 17.4% died. This study analyzes the mortality in hospital; its objectives are to evaluate the prognostic power of edema and anthropometric and biologic indicators and to seek indices that perform better. Receiver operating characteristic curves were established for each parameter under study and for each index constructed. Areas under receiver operating characteristic curves were highest for biologic indicators, and simple indices, obtained by counting the number of risk factors present, performed best. In the absence of biologic parameters, the authors suggest classifying children as at risk of dying when they present with edema and/or with arm circumference of less than 115 mm. When biologic measurements are possible, in addition to edema and arm circumference, the authors suggest taking serum albumin and transthyretin into account. For serum albumin and transthyretin, mortality risk is defined in terms of values of less than 16 g/liter and 6.5 mg/dl, respectively. Children will be classified as at risk of dying when they present with at least two of the four risk factors. The resulting diagnostic test has a high sensitivity (91.2%) and positive and negative predictive values of 40.8% and 97.9%, respectively.

Plasma cytokines, cytokine antagonists, and disease progression in African women infected with HIV-1

OBJECTIVES

To examine the relation of circulating cytokines and cytokine antagonists to the progression of human immunodeficiency virus type 1 (HIV-1) disease.

DESIGN

Cross-sectional analysis.

SETTING

An ambulatory acquired immunodeficiency syndrome (AIDS) research clinic in Kinshasa, Zaire.

PATIENTS

48 women with AIDS, 51 women with HIV infection who were clinically asymptomatic, and 11 female controls who did not have HIV infection, all from Zaire.

MEASUREMENTS

Plasma levels of interleukin-1beta, tumor necrosis factor-alpha (TNF-alpha), interleukin-6, interleukin-8, interferon-gamma, interleukin-1beta receptor antagonist (interleukin-1Ra), and TNF soluble receptor p55 (TNFsRp55) were assayed by specific radioimmunoassays. Plasma levels of interferon-gamma were assayed by commercial enzyme-linked immunosorbent assay. The Wilcoxon rank-sum test was used to assess the significance of mean and median differences between groups.

RESULTS

Of the 48 patients with AIDS, circulating interleukin-1beta was detected in 2, TNF-alpha in 4, interleukin-6 in 3, and interleukin-8 in 12. None of these factors were seen in any of the 11 controls. Median values of interleukin-1beta (320 pg/mL), TNF-alpha (210 pg/mL), and interleukin-8 (750 pg/mL) were elevated in HIV-infected asymptomatic patients compared with patients with AIDS (2-, 2.6-, and 18.7-fold higher, respectively; P < 0.001). Interleukin-1Ra and TNFsRp55 levels were substantially higher than interleukin-1beta and TNF-alpha levels in HIV-infected asymptomatic patients (73- and 14-fold, respectively) and were higher than those in patients with AIDS (17.8- and 1.74-fold, respectively).

CONCLUSION

High circulating levels of the proinflammatory cytokines interleukin-1beta and TNF-alpha, combined with an excess of their natural inhibitors interleukin-1Ra and TNF-sRp55, were seen in clinically asymptomatic HIV-1-positive African women but not in African women with AIDS or in HIV-negative controls. Circulating cytokine antagonists may play a clinical role in modulating cytokine-associated symptoms in the early phases of HIV infection.

[Increasing use of cesarean section, even in developing countries]

At Kaziba hospital in rural Zaire, the frequency of deliveries by Caesarean section rose from 6.2% in 1971 to 12% in 1992, and the fraction of repeated sections rose from 17% to 49%. During the same period, the overall maternal mortality decreased from 0.3% to 0.12%, and deaths connected with Caesarean section from 3.2% to 0.7%, but still the risk of dying remained 13 times higher for births by Caesarean section compared with vaginal deliveries. The frequency of vacuum deliveries was halved during the period, and mean birth weight decreased by about 100 g. Perinatal mortality remained at about 2%. Among 760 Caesarean sections performed in the years 1991 and 1992, 93% were emergency cases. Spinal anesthesia was used in 97%, and blood transfusion was given to 4% of the women. The main indications were mechanical (30%), previous Caesarean section (20%), foetal asphyxia (19%), and suspected uterine rupture (10%). Uterine rupture was verified in 37 cases (4.9%), of which 27 were Caesarean scar ruptures. 259 of the operations were performed by a nurse or a dentist. Operations carried out by persons other than physicians were complicated by wound infections at a higher rate (20.8%) than those carried out by experienced doctors (11.2%). In areas with a poorly developed health system, a high rate of Caesarean section represents a hazard to maternal health. The need for knowledge about alternative methods like vaginal extraction, symphyseotomy and active management of labour is underlined.

The male versus female perspective on family planning: kinshasa, zaire

Males have often been neglected in both family planning programmes and in surveys used to design and evaluate such programmes. A 1988 study on fertility, family planning and AIDS in Kinshasa, Zaire, provides comparable data on 3140 men and 3485 women of reproductive age which served as the basis for analysing male/female differences. The study indicated a fair degree of similarity in the attitudes, beliefs, knowledge levels and practices of men and women regarding fertility and family planning. Where they differed (e.g. on expected or ideal number of children, the desire for more children at parity 7 or above), men tended to be more pronatalist than women. The implications of the findings for future family planning programmes are discussed. Programmes should target males because of their role as decision makers within Zairian society.

Using community health workers for malaria control: experience in Zaire

The potential for using community health workers (CHW) for administering timely and effective treatment for presumptive malaria attacks was evaluated in the Katana health zone in Zaire. In each of the 12 villages of an intervention area (area A) with 13000 inhabitants, a CHW was trained in the use of a simple fever management algorithm. The CHWs performed their services under the supervision of the nurse in charge of the area's health centre (HC). Malaria morbidity and mortality trends were monitored during 2 years in area A and in an ecologically comparable control area (area B), where malaria treatment continued to be available at the HC only. Health care behaviour changed dramatically in the intervention area, and by the end of the observation period 65% of malaria episodes were treated at the community level. Malaria morbidity declined 50% in area A but remained stable in the control area. Parasitological indices showed similar trends. Malaria-specific mortality rates remained, however, at essentially the same levels in both areas. The non-comprehensiveness of the CHWs' care and their ambiguous position in the health care system created problems that compromise the sustainability of the intervention.

The role of an anaesthetist in a field hospital during the cholera epidemic among Rwandan refugees in Goma

In 1849 John Snow, already the leading anaesthetic practitioner and innovator of his day, made a historic contribution to the epidemiology of infectious disease by his famous study of the distribution of cholera around the area of Broad Street in London. We report on our experience as anaesthetists in a field hospital, dispatched as part of the international rescue effort to Goma, Zaire, to help combat the effects of cholera among the Rwandan refugees.

[Generalized molluscum contagiosum in an African child with AIDS]

A 12-year-old girl from Zaire with AIDS (CDC: P2 D1) presented with a generalized molluscum contagiosum infection. She had suffered from systemic cryptococcosis and from cryptosporidiosis several months before admission. While molluscum contagiousum infection is usually a self-limiting disease in immunocompetent persons, a fulminant appearance and persistence of giant mollusca occurs with advanced immunodeficiency. Histological and immunohistological examinations showed a severe diminution of Langerhans and T cell populations that might enhance the dissemination of the infection. Molluscum-like lesions of cryptococci have been described, and cutaneous cryptococcosis is the main condition to be considered in the differential diagnosis. Further differential diagnoses should include American and African histoplasmosis, and the cutaneous manifestations of mycobacterial infections, of toxoplasmosis and of Pneumocystis carinii infection.

Premarital sexual experience of married women in Kinshasa, Zaire

Using responses from questions about age at first sexual intercourse and age at first marriage, this paper offers a method of studying premarital sexual behaviour in societies where the subject is a taboo topic. More than half of the currently married women in Kinshasa engaged in sexual intercourse before marriage. The likelihood of having premarital intercourse increases among younger women, those with higher education, and those whose ethnic groups have liberal attitudes towards sexual conduct. The results also suggest that sexual activity accounts for late marriage.

Neuropsychiatric HIV-1 infection study: in Kenya and Zaire cross-sectional phase I and II

The objective of the study was to determine the prevalence and natural history of human immunodeficiency virus type 1 (HIV-1) associated psychiatric, neuropsychological and neurological abnormalities. A total of 408 subjects were recruited in Nairobi and Kinshasa. The study consisted of a cross sectional phase and a longitudinal follow up. Assessment was made by a data collection instrument including six modules. The intercentre and intracentre reliability in the use of the each module have been formally evaluated. The mean global score on the Montgomery-Asberg Depression Rating Scale was significantly higher in symptomatic seropositive individuals than in matched seronegative controls. In conclusion, these data suggest that the risk of subtle cognitive deficits may be increased in asymptomatic stages of HIV-1 infection.

Epidemic spread of plasmid-mediated tetracycline resistant Neisseria gonorrhoeae in Zaire

A cohort of 650 prostitutes from Kinshasa, Zaire, was followed at monthly intervals for sexually transmitted diseases as part of an HIV intervention project. Neisseria gonorrhoeae isolates, obtained during a period of 30 months, were auxotyped, serotyped and tested for antimicrobial susceptibility. Among 1085 gonococcal isolates tested, 725 (67%) produced beta-lactamase (PPNG) and 323 (30%) showed plasmid-mediated resistance to tetracyline (TRNG). Over time, the prevalence of PPNG varied between 60 and 73%, while the level of TRNG increased from 11 to 45%.

HIV seroprevalence in healthy blood donors in northeastern Zaire

Despite high seroprevalence rates in some parts of Africa, there is notable variation in prevalence between population subgroups. To document changes and trends in HIV seroprevalence in northeastern Zaire, 1989 to 1992 blood donor data were reviewed. Overall, 2453 donors were tested with seropositivity varying from 2.8% in 1989 to 6.9% in 1992. The increase in seropositivity was significant for men (2.5 to 5.8%, P = 0.017) and for people residing in rural areas (2.0 to 6.1%, P = 0.0008) but not for women (5.4 to 8.6%, P = 0.15) nor for urban individuals (10.5 to 8.6%, P = 0.55). These findings suggest that: 1) HIV infection is spreading in previously less-affected population subgroups rather than increasing widely in the entire population, 2) the HIV epidemic could be reaching a plateau or endemic phase in northeastern Zaire, and, 3) continued blood donor screening and wise transfusion practices are needed.

A preliminary evaluation of the cognitive and motor effects of pediatric HIV infection in Zairian children

Fourteen asymptomatic HIV-infected Zairian children under 2 years of age displayed social and motor developmental deficits on the Denver Developmental Screening Test when compared with 20 HIV-negative cohorts born to HIV-infected mothers and 16 control children. In a second study, 11 infected children over 2 years of age had sequential motor and visual-spatial memory deficits on the Kaufman Assessment Battery for Children and motor development deficits on the Early Childhood Screening Profiles. HIV infection affects central nervous system structures mediating motor and spatial memory development, even in seemingly asymptomatic children. Furthermore, maternal HIV infection compromises the labor-intensive provision of care in the African milieu and undermines global cognitive development in even uninfected children.

A preliminary evaluation of the cognitive and motor effects of pediatric HIV infection in Zairian children

Fourteen asymptomatic HIV-infected Zairian children under 2 years of age displayed social and motor developmental deficits on the Denver Developmental Screening Test when compared with 20 HIV-negative cohorts born to HIV-infected mothers and 16 control children. In a second study, 11 infected children over 2 years of age had sequential motor and visual-spatial memory deficits on the Kaufman Assessment Battery for Children and motor development deficits on the Early Childhood Screening Profiles. HIV infection affects central nervous system structures mediating motor and spatial memory development, even in seemingly asymptomatic children. Furthermore, maternal HIV infection compromises the labor-intensive provision of care in the African milieu and undermines global cognitive development in even uninfected children.

Gonorrhea as a risk factor for HIV acquisition

OBJECTIVE

The role of gonorrhea in facilitating acquisition of HIV infection has only recently been studied. A previous nested case-control analysis in a cohort of female sex workers in Zaïre found a strong association between HIV seroconversion and prior gonorrheal infection. The objective of this study was to replicate the Zaïre study analysis in a cohort of 273 Cameroonian sex workers to determine whether gonorrhea increased the risk of HIV acquisition, and if the crude association between gonorrheal infection and HIV acquisition was weakened when the level of unprotected coitus was more carefully controlled.

METHODS

We conducted a nested case-control study of initially HIV-1-negative women (n = 273) followed prospectively (with monthly sexually transmitted disease check-ups and 3-monthly HIV-1 serology). As in Zaïre, cases (seroconverters, n = 17) were compared with controls (women who remained HIV-1-negative, n = 68) for incidence of gonorrhea and sexual exposure during the presumed period of HIV-1 acquisition.

RESULTS

The association between gonorrheal infection and subsequent HIV acquisition was stronger in Zaïre than in Cameroon [crude odds ratios (OR), 6.3 versus 2.2]. In both the Zaïre and Cameroon data the crude OR were reduced (6.3 to 4.8, and 2.2 to 1.7, respectively) by controlling for risk factors including a dichotomous variable indicating irregular or no condom use. When this variable was replaced in the Cameroon data with a more precise continuous variable indicating the percentage of unprotected coital acts, the gonorrhea OR was further reduced to 1.4 (95% confidence interval, 0.4-4.9).

CONCLUSION

These results suggest that in the Cameroon cohort, gonorrheal infection did not facilitate HIV acquisition, but that having gonorrhea was a marker for unprotected coitus that facilitated HIV acquisition. The data demonstrate how OR can be overestimated when imprecise dichotomous measures of unprotected coitus are used. Future studies should plan for better control of self-reported condom use.

Methodological approaches in a baseline study of diarrhoeal morbidity in weaning-age children in rural Zaire

A community-based prospective study of diarrhoeal morbidity of weaning-age children in 18 geographically separate village clusters was conducted as the baseline phase of a controlled trial of a hygiene education intervention to reduce diarrhoeal diseases in rural Zaire. For 12 weeks trained interviewers collected information at weekly home visits about the diarrhoeal morbidity of 2082 children aged 3-35 months. Included in the analyses were 1914 children (92%) with 9 or more complete weeks of data. Mothers' reporting of the existence or otherwise of episodes appeared reliable, and more than 70% of children had at least one episode of diarrhoea during the 12-week study period, the mean number of episodes being 1.9 per child. Reporting of the start and termination of diarrhoeal episodes was, however, irregularly distributed among the 7 days between successive home interviews, with 36% of all episodes reported as starting on interview days, and 29% reported as ending the day before an interview: in each case, only 14% would have been expected. After adjusting for these reporting biases, 61% of the episodes lasted 2-4 days, but a number of very long duration were also reported, and the mean duration of the episodes was 4.8 days. Children, had, on average, 9.2 days of diarrhoea during the study period. Contrasts with previous characterizations of reporting error in diarrhoeal studies are noted.

Community-based hygiene education to reduce diarrhoeal disease in rural Zaire: impact of the intervention on diarrhoeal morbidity

BACKGROUND

Diarrhoeal disease is a leading cause of morbidity in young children in rural Zaire. Few diarrhoea prevention programmes have been implemented in Bandundu Province, where available data suggest an annual prevalence rate of 10%. The urgent need to reduce diarrhoeal morbidity in Zaire, together with the potential effectiveness and feasibility of hygiene education as a diarrhoea prevention strategy, led to the development of the present research project.

METHODS

A randomized, controlled trial of an education intervention to reduce diarrhoea through improved personal and domestic hygiene behaviours was conducted in 18 geographically separate village clusters (sites) in rural Zaire. For 12 weeks baseline information on the diarrhoeal morbidity of 2082 children aged 3-35 months was collected at weekly home visits, and structured observations of hygiene practices related to diarrhoea were made on a subset of 300 families. Intervention messages addressed disposal of animal faeces from the yard, handwashing after defecation and before meal preparation and eating, and disposal of children's faeces. Three months after the start of the intervention and exactly 1 year after the baseline studies, a second diarrhoeal morbidity study and a second observational study were conducted in order to evaluate the intervention.

RESULTS

Children in intervention communities experienced an 11% reduction in the risk of reporting diarrhoea during the peak diarrhoeal season, compared to controls (P < 0.025). The largest differences were seen among children aged 24-35 months, with those from intervention communities reporting significantly fewer episodes, shorter mean durations and hence fewer days of diarrhoea. There was some evidence that greater reductions in diarrhoea occurred in sites where the quality of the intervention, a scored measure of volunteer efficacy and community participation, was highest.

CONCLUSIONS

The results of this study suggest that hygiene education may be an effective approach to reduce the incidence and duration of diarrhoeal episodes in rural Zaire. Children aged 2 years appear to benefit the most. A Hawthorne effect of the education may contribute to diarrhoeal reductions.

Anti-A60 immunoglobulin G in the serodiagnosis of tuberculosis in HIV-seropositive and seronegative patients

OBJECTIVE

A60 is a high molecular weight mycobacterial antigen complex. The detection of immunoglobulin (Ig) G antibodies to A60 has been advocated as a reasonably sensitive and specific test for active tuberculosis (TB). We aimed to compare the sensitivity of this test among HIV-seropositive and HIV-seronegative patients with pulmonary TB.

METHODS

The presence and concentration of anti-A60 IgG antibodies was assessed by enzyme-linked immunosorbent assay in 208 HIV-seropositive and 91 HIV-seronegative Zaïrian patients with smear-positive pulmonary TB. The relationship between anti-A60 IgG levels and HIV serostatus, CD4+ lymphocyte counts, presence of clinical AIDS, and tuberculin skin test results was verified.

RESULTS

Only 36.5% of the HIV-seropositive, compared with 69.2% of the HIV-seronegative patients had a positive anti-A60 IgG test (P < 0.00001). Among HIV-seropositive patients, anti-A60 IgG levels did not differ according to CD4+ lymphocyte counts, presence of clinical AIDS, or tuberculin skin test results.

CONCLUSIONS

Among patients with pulmonary TB, the sensitivity of testing for anti-A60 IgG was much lower among HIV-seropositive than among HIV-seronegative patients, even from the early stages of HIV-related immunodeficiency. This limits the utility of anti-A60 IgG-antibody testing in the diagnosis of TB among HIV-infected patients.

Condom promotion, sexually transmitted diseases treatment, and declining incidence of HIV-1 infection in female Zairian sex workers

The control of sexually transmitted diseases, including HIV-1, among sex workers and their clients in urban areas in developing countries, is considered a valuable and cost-effective intervention to contain the spread of HIV-1. The effect of a programme of STD treatment combined with condom promotion on HIV-1 incidence has so far not been measured. During an intervention including condom promotion, as well as monthly sexually transmitted disease screening and treatment among 531 initially HIV-1 negative female sex workers in Kinshasa, Zaire, 70 became infected with HIV-1 (incidence of 8.0 per 100 women-years [wy]). A decline of HIV-1 incidence was observed over time, from 11.7/100 wy during the first 6 months, to 4.4/100 wy over the last 6 months, 3 years later (p = 0.003). Simultaneously, regular use of condoms with clients went up from 11% to 52% and 68%, after 6 and 36 months of intervention, respectively. Risk factors for HIV-1 seroconversion after multivariate analysis included irregular condom use (RR 1.6 [95% Cl 1.1-2.8]), gonorrhoea (RR 2.5 [1.1-6.4]), trichomoniasis (RR 1.7 [1.1-2.8]), and genital ulcer disease (RR 2.5 [1.1-6.4]), during the probable period of acquisition of HIV-1. In women who attended more than 90% of their clinic appointments, the HIV-1 incidence was 2.7/100 wy compared to 7.1, 20.3, and 44.1 per 100 wy among women who attended 76-90%, 50-75%, and less than 50% of the monthly appointments, respectively (p < 0.0001). These trends remained after controlling for reported condom use and number of clients. This study confirms earlier findings that STDs facilitate transmission of HIV-1 and shows that a clinic-based intervention consisting of STD care and condom promotion can result in a major decline of HIV-1 incidence among female sex workers.