Aim: Cryptococcosis is
azoonotic infection caused by fungal of the Cryptococcus neoformans
complex comprising of C. neoformans and C. gattii. The disease
affects humans and animals worldwide causing morbidity and mortality. This work
was carried out to determine the occurrence of cryptococcal antigens and factors
associated with presence of antigens in cattle in Zaria, Nigeria.
and Methods: Three hundred and ninety (390) serum samples from cattle of
various ages were collected from 11 farms in Zaria, Nigeria. The samples were
analysed using a latex agglutination test and lateral flow assay kit which
detects the polysaccharide capsular antigens of Cryptococcus species.
Results: Out of the 390 samples tested 28 (7.17%) were found to be positive
using the latex agglutination test while only of these 22 (5.64%) were positive
using the lateral flow assay. There was a strong correlation (r=0.939, p=0.0002)
between the results of the latex agglutination test and the lateral flow assay.
There was no statistically significant difference (p>0.005) in positivity
for cryptococcal antigens between sex, age and sex, though, there was a
statistically significant difference (p<0.05) in positivity between
management systems i.e. semi-intensive and intensive farming systems.
Conclusions: The epidemiological value of this report lies in its
demonstration that the risk of cattle and humans infection with cryptococcosis
exist in farms in Zaria. The presence of this pathogen among these cattle poses
an economic threat to the livestock industry due to the mastitis it causes. It
also poses a significant public health threat because of its zoonotic nature and
the increasing population of immunocompromised individuals. Large scale studies
to determine specific risk factors and the role of the environment and
experimental studies to determine what governs the transition from nasal
colonisation to infection are recommended.
Keywords: cattle, cryptococcus
antigens, lateral flow assay, latex agglutination, Nigeria, sera, Zaria.