G. C. Ejezie

Efficacy of a combination of praziquantel and artesunate in the treatment of urinary schistosomiasis in Nigeria

The combined effects of praziquantel and artesunate in the treatment of urinary schistosomiasis were assessed among 312 randomly selected schoolchildren aged 4-20 years in Adim community, Nigeria. In the preliminary screening, infection was confirmed in 327 (38.5%) of the 850 subjects screened. Infected subjects who reported for treatment were then divided into six treatment groups of 52 subjects each; 44 subjects in each group completed their treatment regimens and submitted their urine for post-treatment assessment. Praziquantel and artesunate were administered orally at 40 mg/kg and 4 mg/kg body weight, respectively. Adverse effects due to drug reactions were assessed 72 h after medication and all perceived episodes of illness were treated. Morbidity indicators were assessed 56 days after the final dose of the drug regimens. All treatment regimens were well tolerated. The cure rates were 72.7% in the praziquantel plus placebo-treated group and 70.5% in the artesunate plus placebo group, while the artesunate plus praziquantel group had the highest cure rate (88.6%). Haematuria and proteinuria were extensively reduced after treatment with the three drug regimens. This study confirmed that the treatment of urinary schistosomiasis with the combination of praziquantel and artesunate is safe and more effective than treatment with either drug alone.

Modification of behaviour and attitude in the control of schistosomiasis. 1. Observations on water-contact patterns and perception of infection.

Observations on the water-contact patterns of 2136 residents of Admin community in Nigeria were conducted at four streams between February 1993 and January 1994. Urine samples collected from those observed were used to estimate the prevalence and intensity of Schistosoma haematobium infection. A questionnaire was also completed for each of the subjects, to test their perception of urinary schistosomiasis and its transmission. Infection was detected in 1076 (50.4%) of the subjects, with peak prevalence among those aged 10-14 years. Intensity of infection was more closely correlated with the number of water contacts (r = 0.97) than with the total duration of the exposure (r = 0.77), emphasising the importance of specific/multiple activities, and of the surface area of the body submerged, in transmission. One stream (Culvet) was identified as the main transmission point, with bathing/swimming and fishing as the main activities predisposing people to infection. The awareness of urinary schistosomiasis and its symptom (blood in urine) were high but specific knowledge about the parasite, its vector and the interaction between the parasite and vector in the parasites life-cycle were extremely low. Activities that require behaviour and attitude modification have been identified and encouraged as components in the control of schistosome-attributable morbidity (in the absence of pipe-borne water).

School-based schistosomiasis control programmes: a comparative study on the prevalence and intensity of urinary schistosomiasis among Nigerian school-age children in and out of school

A cross-sectional study was conducted in February 1998 on the prevalence and intensity of urinary schistosomiasis among school-age children in and out of school at Adim village in Nigeria to test the objective of delivering a control programme through the school system. School enrollment figures and non-attendance rate were collated from questionnaires that were self-administered by heads of families. Prevalence and intensity of infection were determined following filtration of urine and counting of carbol fuchsin-stained eggs of Schistosoma haematobium. The rates of regular school attendance, irregular attendance and non-attendance were 69.1%, 5.1%, and 25.8%, respectively. These indices were not significantly associated with the age of the schoolchildren (P > 0.05). Boys (76.6%) were more associated with regular attendance than girls (61.4%) (P < 0.0001) while girls had a higher rate of non-attendance (32.7%) than males (19.1%) (P < 0.0001). Although more out-of-school children were infected (90.7%) than those in school (86.8%), the difference was not statistically significant (P > 0.05). The same association was established in the variation of mean egg count between the 2 study populations though intensity was higher among out-of-school children. The principal reasons proffered for the high rate of non-attendance listed in their order of importance were: economic, sickness, poor performance, refusal, farming and fishing. A dual method of control that would in incorporate the integration of recognized local authorities is suggested in areas with moderate school attendance rate like Adim, as lack of treatment of infected out-of-school children ensures continuous contamination and re-infection.

Congenital malaria in Calabar, Nigeria: the molecular perspective.

Polymerase chain reaction (PCR) has been shown to be more sensitive in detecting low-level parasitemia than conventional blood film microscopy. We estimated the prevalence of congenital malaria using nested PCR amplification of the small subunit 18S RNA gene to detect low-level parasitemia and identify Plasmodium species in 204 mother-neonate pairs. Cord-blood parasitemia was detected in four babies by PCR, giving a prevalence of 2.0%. The newborns of primidgravidae were more susceptible to congenital malaria than those of multigravidae (P < 0.0001). There was a strong correlation between placental malaria and congenital malaria (odds ratio = 10.1, 95% confidence interval = 1.3-76.1, P = 0.0487). We conclude that the prevalence of congenital malaria in Calabar detected by PCR is lower than has been reported in this environment through microscopy.

Enterobiasis and its relationship with anal itching and enuresis among school-age children in Calabar, Nigeria

Abstract The prevalence of enterobiasis and its relationship with anal itching and enuresis were investigated among 799, randomly selected children aged 5–14 years, who lived, either in an area of high population density or one with a much lower population density, in Calabar, Nigeria. The eggs of Enterobius vermicularis were found in anal swabs (collected with transparent adhesive tape) from 60 (7.5%) of the subjects tested, with the prevalence of infection appearing markedly higher in the 403 children from the area with a high population density than in the 396 from the less densely populated area (11.7% v. 3.3%; P<0.05). Questionnaire-based interviews were used to determine which of the children suffered from anal itching, enuresis or both. Compared with the egg-negative subjects, the 60 children who were egg-positive for Enterobius were found to be much more likely to be suffering from anal itching (78.3% v. 28.3%; P<0.05) or enuresis (53.3% v. 36.4%; P<0.05). Enterobiasis is therefore not a problem that is restricted to the temperate regions of the world, and may be a cause of enuresis or at least a contributory factor in the development of this complaint.

The Role of Kola Nut (Cola Nitida) in the Etiology of Malaria Morbidity

The contribution of kola nut in mimicking malaria-like morbidity in apparently healthy volunteers was evaluated. Thirty-five grams of Cola nitida was given to each of the 48 volunteers who were known not to have taken kola nut or coffee in the previous one month for three consecutive days. The blood samples of these volunteers were enumerated for malaria parasites before serving them the kola nut. The sampling of blood was repeated on the 2nd and 3rd days for the presence of malaria parasites. Blood samples were also taken from known kola nut addicts (those that eat kola nut on daily basis). It was found that 16 (33.3%) of the volunteers had malaria parasites in their blood at the inception of the study while 32 (66.7%) had no detectable parasites. Four days after, 10 (20.8%) of the volunteers that did not show detectable parasites on the first day now had parasites. Those that showed detectable parasite before taking the kola had significant increase in parasite density. Statistical analysis showed a strong relationship between parasite increase and eating of the kola nut (Chi-squared, X 2 = 14.83, p > 0.0001 at 95% confidence limit). The volunteers reported clinical symptoms of sleeplessness, lack of concentration, dizziness, and weakness observable in malaria patients. There was no association between malaria parasite presence and clinical complaints (X 2 = 3.75, df = 1, p = 0.05). It was found that 11 people without the malaria parasite in their blood before and after taking the kola nut complained of various malaria symptoms confirming that kola nut can mimic malaria-like symptoms. In conclusion, it can be said that kola nut taken at a high concentration (about 35 g/day) will mimic malaria-like symptoms. This quantity will leave a high level of caffeine and cyanide in the circulation so that people with a low level of malaria parasite in them will notice active infection which otherwise may have been controlled by the host immune system. Lastly, the observed phenomenon can affect drug pressure and induce resistance to antimalarial drugs. The mechanism of kola nut action that influences malaria-like morbidity is discussed.