Study of antigen HBs and antivirus antibodies of hepatitis C during hepatopathies in Mali

A prospective study carried out in Bamako, Mali between July 1998 and January 1999 has assessed the seroprevalence of hepatitis C virus (HCV) in 91 carrier patients of chronic hepatopathy at a cirrhrosis stage (53) or of hepato-cellular carcinoma (38) and to compare with in 92 blood donors as a control population. Only seroprevalence confirmed by a complementary test has been taken into account (RIBA). HCV seroprevalence reached 25% including all hepatopathies, 24% in cirrhrosis and 26% in hepato-cellular carcinomae (HCC) versus 4% in blood donors. Antigen HBs of hepatitis B virus has been found in 55% of patients, versus 25% of the control cases (p = 0.0006). On the whole, the two markers have been notified a little more often in HCC than in cirrhosis and the combination of the two markers has been more frequent during cirrhosis as well. The role of HCV played in cirrhosis and HCC onset in Mali appears to be important.     

Herpes simplex virus and HIV-1: deciphering viral synergy

Recent proof-of-concept randomised controlled trials have shown a causal relation between herpes simplex virus (HSV) type 2 infection and HIV-1 replication in co-infected individuals. We explore the mechanisms that may operate to enhance reciprocal viral replication. Direct interactions could involve HIV-1-related immune deficiency, disruption of mucosal barrier by HSV infection/reactivation, HSV-induced mucosal cell recruitment, transactivation of HIV-1 replication by HSV proteins, and immune modulation by HSV decoys. Indirect interactions might coexist through disturbances of the vaginal flora during HSV shedding and systemic immune activation. In co-infected individuals, suppressive HSV treatment reduces HIV-1 genital and systemic excretion. This finding is a likely result of efficacious prevention of HSV2 reactivations, and perhaps of other herpesviruses. Strategies to control HSV2 and other herpesviruses deserve urgent attention and should become part of the HIV-1 prevention and care package.     

The impact of introducing new vaccines on the health system: Case studies from six low- and middle-income countries

Objective

We aimed to explore the impacts of new vaccine introductions on immunization programmes and health systems in low- and middle-income countries.

Methods

We conducted case studies of seven vaccine introductions in six countries (Cameroon, PCV; Ethiopia, PCV; Guatemala, rotavirus; Kenya, PCV; Mali, Meningitis A; Mali, PCV; Rwanda, HPV). Interviews were conducted with 261 national, regional and district key informants and questionnaires were completed with staff from 196 health facilities. Routine data from districts and health facilities were gathered on vaccination and antenatal service use. Data collection and analysis were structured around the World Health Organisation health system building blocks.

Findings

The new vaccines were viewed positively and seemed to integrate well into existing health systems. The introductions were found to have had no impact on many elements within the building blocks framework. Despite many key informants and facility respondents perceiving that the new vaccine introductions had increased coverage of other vaccines, the routine data showed no change. Positive effects perceived included enhanced credibility of the immunisation programme and strengthened health workers’ skills through training. Negative effects reported included an increase in workload and stock outs of the new vaccine, which created a perception in the community that all vaccines were out of stock in a facility. Most effects were found within the vaccination programmes; very few were reported on the broader health systems. Effects were primarily reported to be temporary, around the time of introduction only.

Conclusion

Although the new vaccine introductions were viewed as intrinsically positive, on the whole there was no evidence that they had any major impact, positive or negative, on the broader health systems.     

Diagnostic à l’échographie Doppler d’une fistule artérioveineuse rénale post-biopsie: Intérêt pour le milieu tropical

We report the case of a 37-year-old woman who had previously undergone percutaneous renal biopsy and in whom color duplex Doppler ultrasonography revealed an arteriovenous fistula associated with a false aneurysm of the lower interlobar artery of the right kidney. The fistula was treated with embolization in a specialized center in North America. At follow-up, the false aneurysm was monitored by Doppler ultrasonography until it resolved spontaneously. We emphasize the valuable and decisive role of color Doppler ultrasound for the diagnosis of arteriovenous fistulas following percutaneous renal biopsy in a tropical environment where the choice of equipment is limited by financial constraints.     

Do antibody responses to malaria vaccine candidates influenced by the level of malaria transmission protect from malaria?

Objectives To examine whether the humoural response to malaria vaccine candidate antigens, Plasmodium falciparum [circumsporozoite repetitive sequence (NANP)₅ GLURP fragments (R0 and R2) and MSP3] varies with the level of malaria transmission and to determine whether the antibodies (IgG) present at the beginning of the malaria transmission season protect against clinical malaria. Methods Cross‐sectional surveys were conducted to measure antibody response before, at the peak and at the end of the transmission season in children aged 6 months to 10 years in two villages with different levels of malaria transmission. A cohort study was performed to estimate the incidence of clinical malaria. Results Antibodies to these antigens showed different seasonal patterns. IgG concentrations to any of the four antigens were higher in the village with high entomological inoculation rate. Multivariate analysis of combined data from the two villages indicated that children who were classified as responders to the selected antigens were at lower risk of clinical malaria than children classified as non‐responders [(NANP)₅ (incidence rate ratio (IRR) = 0.65, 95% CI: 0.46–0.92; P = 0.016), R0 (IRR = 0.69, 95% CI: 0.48–0.97; P = 0.032), R2 (IRR = 0.73, 95% CI: 0.50–1.06; P = 0.09), MSP3 (IRR = 0.52, 95% CI: 0.32–0.85; P = 0.009)]. Fitting a model with all four antibody responses showed that MSP3 looked the best malaria vaccine candidate (IRR = 0.63; 95% CI: 0.38–1.05; P = 0.08). Conclusion Antibody levels to the four antigens are affected by the intensity of malaria transmission and associated with protection against clinical malaria. It is worthwhile investing in the development of these antigens as potential malaria vaccine candidates.