Wuchereria bancrofti in a community with seasonal transmission: stability of microfilaraemia, antigenaemia and filarial-specific antibody concentrations
Wg. Jaoko et al., Wuchereria bancrofti in a community with seasonal transmission: stability of microfilaraemia, antigenaemia and filarial-specific antibody concentrations, ANN TROP M, 95(3), 2001, pp. 253-261
Citations number
20
Categorie Soggetti
Envirnomentale Medicine & Public Health","Medical Research General Topics
The effect of seasonal transmission on microfilaraemia, antigenaemia and fi
larial-specific antibody levels in individuals infected with Wuchereria ban
crofti was investigated in a follow-up study in an endemic community in nor
th-eastern Tanzania. The subjects were 37 adult male residents who were fou
nd to be positive for circulating filarial antigen (CFA) at the beginning o
f the study (26 of whom were also found microfilaraemic with W. bancrofti a
t this time). Blood samples were collected from each subject in July 1998,
January 1999 and July 1999, during the seasons when transmission intensity
was high, low and high, respectively. The mean intensities of microfilaraem
ia and the mean concentrations of CFA were each slightly higher during the
low-transmission season than during the two high-transmission seasons but t
he differences were not statistically significant (P>0.05). Similarly, the
mean levels of filarial-specific IgG(1), IgG(2), IgG(3), IgG(4) or IgE did
not differ to a statistically significant degree between the three examinat
ion times. Microfilaraemias and the levels of CFA and filarial-specific ant
ibodies all therefore appeared to be remarkably stable and largely unaffect
ed by the seasonal variation in transmission. That no variation in the mean
IgG(4)/IgE ratio was observed over the study period may indicate that the
level of resistance to W. bancrofti infection in the study subjects was als
o unaffected by the transmission season.