01854nas a2200361   4500000000100000008004100001653002900042653002100071653003000092653002200122653001500144653001900159653002400178653001600202653001700218653000900235653001100244653001100255653001100266653001200277653000900289653002100298653001000319653001500329100001700344700001500361700001500376245006200391300000900453490000700462520100900469022001401478       1995                            d10aSkin Diseases, Parasitic10aSex Distribution10aResidence Characteristics10aRandom Allocation10aPrevalence10aonchocerciasis10aOnchocerca volvulus10aMiddle Aged10aMicrofilaria10aMale10aMalawi10aHumans10aFemale10aAnimals10aAged10aAge Distribution10aAdult10aAdolescent1 aCourtright P1 aJohnston K1 aChitsulo L00aA new focus of onchocerciasis in Mwanza District, Malawi.  a34-60 v893 a<p>Anecdotal information suggested that a new focus of onchocerciasis had recently developed in Mwanza in Malawi, a district not contiguous with Thyolo, the only district in Malawi with recognized autochthonous transmission. We carried out a survey of the northern half of Mwanza district, randomly selecting 62 villages for assessment. Two iliac crest skin snips were taken from 2215 residents over the age of 15 years; one-quarter had Onchocerca volvulus microfilariae. Prevalence increased with age and was higher overall among men than women. The age-adjusted prevalence among migrants from Thyolo was 31%. Among residents who had never been outside Mwanza, the gender-specific prevalences and microfilarial loads were similar. The intensity of infection was low. Autochthonous transmission of O. volvulus has thus been demonstrated in Mwanza and illustrates the possibility of the spread of the disease to new foci in Malawi and the surrounding countries, due to significant population shifts.</p>
  a0035-9203