Abstract:
Leptospirosis caused by spirochete bacterium of genus Leptospira affects humans and animals
worldwide. Rodents are major reservoirs of leptospires whereas wetland and aquatic migratory birds also
carry and transmit leptospires. Leptospirosis studies in fish are lacking in African countries despite
favourable environment and abundant reservoirs, which can spread leptospires into aquatic habitats and
infect fish. The objectives of this study were to determine presence of Leptospira in fish; the prevalent
Leptospira serovars and whether are related to serovars reported in animals; and to ascertain potential
public health risk. Live tilapia, catfish and eel fish (n=48) were caught in Mindu Dam in Morogoro
Municipality in eastern Tanzania. Blood sample was collected using syringes and needles to obtain serum
for serological detection of leptospirosis using gold standard microagglutination test utilizing local and
reference Leptospira serovars Sokoine, Kenya, Pomona and Hebdomadis. Twenty-six fish (54.2%) were
positive for serovar Kenya (29.2%) and Sokoine (25%). Leptospira prevalence was high in both catfish (58.3%)
and tilapia fish (47.8%). Thus, different fish types are infected with Leptospira found in animals. Fish could
be source of Leptospira infection to humans since tilapia and catfish are the common fish type widely
consumed in Tanzania. Further study covering lakes, rivers and dams is required to better understand the
prevalence of Leptospira in fish and actual public health threats.
