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A Nasidi

Publications and source records attributed to A Nasidi.

25 records · Page 2Linked to original sources
PubMedDate not supplied

Urban yellow fever epidemic in western Nigeria, 1987.

A large epidemic of urban yellow fever occurred in April and May 1987 in Oyo State, western Nigeria. The principal vector was Aedes aegypti, breeding in domestic water containers. The 1987 outbreak followed an epidemic of sylvatic yellow fever in eastern Nigeria the previous year, and probably resulted from introduction of the virus by viraemic travellers. The outbreak in Oyo State ended in early July, by which time 805 cases and 416 deaths had been officially notified. However, surveys of 3 villages in the epicentre, a region with over 4 million inhabitants, indicated an infection rate of approximately 20%, a clinical attack rate of 2.9% and a mortality rate of 0.6%, suggesting that the true incidence of cases and deaths far exceeded the official reports. Yellow fever virus was isolated from persons with fully developed yellow fever as well as mild febrile illness. One virus isolate was made from blood of an individual with mild illness, who had received 17D vaccine 5 d earlier; monoclonal antibody analysis showed that the isolate was a wild-type virus. Larval indices of Ae. aegypti were very high; however, low vector competence of the Ae aegypti population may have provided a constraint on spread of the epidemic. In late 1987 a third epidemic appeared in Niger State, northern Nigeria, with 644 reported cases and 149 deaths. The vector(s) involved is (are) unknown.

Adolescent↗
PubMedDate not supplied

Yellow fever vaccination and pregnancy: a four-year prospective study.

During an outbreak of yellow fever (YF) in Nigeria in 1986-1987, women at various stages of pregnancy were vaccinated against YF, either because those pregnancies were not known at the time or because they requested vaccination out of fear of acquiring the disease. This offered an opportunity to assess the safety and efficacy of YF vaccine in pregnant women and the effect of this vaccine on their newborn children. Pre-vaccination and post-vaccination serum samples from the vaccinated pregnant women were tested by enzyme-linked immunosorbent assay and by neutralization tests for antibody to YF virus. The results showed that the antibody responses of these pregnant women were much lower than those of YF-vaccinated, non-pregnant women in a comparable control group. Follow-up of these women and their newborn children for 3-4 years showed no abnormal effect that could be attributed to the YF vaccine, which suggests that vaccination of pregnant women, particularly during a YF epidemic, may not be contraindicated.

Adolescent↗
PubMedDate not supplied

A severe epidemic of meningococcal meningitis in Nigeria, 1996.

A particularly severe epidemic of meningococcal meningitis (cerebrospinal meningitis, CSM) occurred in Nigeria between January and June 1996. There were 109,580 recorded cases and 11,717 deaths, giving a case fatality rate of 10.7% overall. This is the most serious epidemic of CSM ever recorded in Nigeria, and may be the largest in Africa this century. It took over 3 months and the combined efforts of a National Task Force set up by the Federal Ministry of Health, the WHO, UNICEF, UNDP, Médecins Sans Frontières, the International Red Cross and several other non-governmental organizations to bring the epidemic under control. The main control measures centred on active treatment of infected persons, mass vaccination and health education. The exact number of persons treated cannot be ascertained, but there were treatment centres in almost every Local Government Area in the affected States. A study of 1577 patients admitted at the Infectious Diseases Hospital, Kano, showed that 84% of those infected were aged < or = 20 years and that, for the first time, infants aged < or = 2 months were affected. Despite intervention, the case fatality rate of 9.1% among this group of patients was similar to the nationwide figure of 10.7%. Long-acting oily chloramphenicol proved highly effective in the treatment of patients, and its routine use in epidemic CSM is recommended. Over 13 million persons were vaccinated in the course of the epidemic. For the first time, cases of CSM were reported from States south of the 'African meningitis belt', suggesting an extension of the belt. The severity of this epidemic yet again underscores the need for a clear policy regarding control measures aimed at forestalling future epidemics. The availability of the recently developed polysaccharide-protein conjugate vaccine should facilitate a decision on mass vaccination for the prevention of epidemic CSM in Africa.

Adolescent↗
PubMedDate not supplied

Interferon alfa-2a (Roferon-A) in the management of chronic hepatitis B infection: results of an open prospective study in Nigerian patients.

The efficacy and safety of recombinant interferon alfa-2a (rIFN) was evaluated in 26 adult Nigerian patients with chronic hepatitis B infection. Male and female patients with serological evidence of HBV infection (HBsAg and/or HBeAg positive patients) and abnormal liver histology were monitored for six months to confirm chronicity. At the end of the six months screening period eligible patient were enrolled into the study and treated with rIFN 4.5 MIU given three times a week for 6 months. Efficacy was assessed primarily by loss of HBV-DNA and/or HBeAg from serum and secondarily by loss of HBsAg and normalization of the liver histology. Safety was assessed by monitoring the leukocyte and platelet count over the treatment period whilst tolerability was assessed by recording the occurrence of adverse events (adverse drug reaction and intercurrent illness). At the end of therapy the response rate with respect to loss of HBV-DNA was 67% and 100% for HBeAg (i.e. for the six patients who were HBeAg positive at baseline). There was loss of HBsAg in 22.2% of the patients. A significant reduction in inflammation and necrosis scores was found among the 10 patients who had both baseline and term biopsies. The frequency of occurrence of adverse events was 53.8% and the laboratory safety parameters were not significantly affected by therapy (p > 0.05). 19.2% of the enrolled patients were withdrawn from the study prematurely. These results demonstrate that rIFN is effective in the management of CHB infection even in Nigerians. The high success rate associated with HBcAg clearance is particularly noteworthy.

Adult↗
PubMedDate not supplied

Bf S gene frequency in Nigerians with HIV infection.

Complement immunogenetic susceptibility to human immunodeficiency virus (HIV) infection was examined in 40 Nigerians with serological and/or clinical evidence of the infection. A mild increase in C4A null alleles (C4AQO) frequency was observed in the patient group compared to a group of healthy subjects (25 per cent vs 17 per cent) but overall the HIV infected and the reference groups did not differ significantly in the frequency of alleles of C4A or C4B. In contrast, properdin factor B (Bf) S gene frequency was significantly higher in the patients with HIV infection (p less than 0.025). There was a concomitant decrease in Bf F allele and gene frequencies (p less than 0.01, and p less than 0.05), respectively. Furthermore, blank Bf allotypes due to excessive complement consumption were detected in two asymptomatic patients. These findings suggest that Major Histocompatibility Complex (MHC) located complement genes may be important HIV infection. In particular Bf S gene or even C4AQO alleles may be permissive or influence outcome of infection with HIV.

Adult↗
PubMedDate not supplied

[Production of a vaccine against hepatitis B in Africa: the problems and prospects].

Much has been achieved in the field since the time of the development, manufacture, and release of a vaccine against hepatitis B based on the purification and inactivation of hepatitis B surface antigen (HBsAg). Subsequent clinical and field trials demonstrated the immunogenic potency and efficacy of this vaccine and it was hoped that the vaccine would protect millions of people not only from hepatitis B (HB) but possibly also from its sequelae including primary carcinoma of the liver (PCL). This form of liver carcinoma is known to be most prevalent among malignant diseases in men residing in South-East Asia and Africa. The high price of the vaccine is the only obstacle in the way of its large-scale use and achievement of the effective control of this infection. Currently, several South-East Asian countries investigate different approaches to reduce the price of the vaccine against HB to a level acceptable for the population. These approaches include collaboration with reliable companies or institutions of other continents which have the necessary funds and scientific technology. Some of these countries already manufacture a cheaper vaccine against HB or they are just starting it. This paper analyses the attitudes of some African countries to the latest achievements and their efforts directed at the vaccine preparation as well as discusses the situation in them as compared with that in South-East Asia.

Africa↗