Human excreta from households of squatter communities in Singalong and Leveriza, Metro Manila,
Philippines were examined for Cryptosporidium sp. infection. Fecal concentration procedure and the
modified specific Ziehl-Neelsen staining technique were used. Of the 54 positive cases, 30 and 24 cases were
detected in solid and semisolid excreta, respectively, with the infection rate being significantly higher (p=
0.008) in Singalong. Oocysts were detected among 53.7% children (≤10 years old) compared to 46.3% in
older age groups. The gender associated difference in infection rate in both study sites was insignificant.
Oocysts density ranged from very few to moderate to numerous. While the results confirmed the
susceptibility of both genders and of all age groups to Cryptosporidium sp., the difference in percent
infection between children and older age groups could not be clearly established owing to the small sampled
population. In the absence of information on the health status of the respondents upon fecal collection, no
association can be made on the pathogenicity of the parasite. We therefore recommend educating the
communities on the risks of them contacting waterborne infections through contaminated waters and
providing them overall improvement in basic sanitary facilities.
Serum total protein, albumin and albumin globulin ratio were determined in Yankasa sheep experimentally
infected with Trypanosoma congolense and immunomodulated with levamisole. The packed cell volume
decreased significantly (P<0.05) between the infected groups with and without immunodulation with
levamisole when compared to the controls. Serum total protein and albumin decreased significantly (P<0.05)
in the infected groups with and without immunomodulation when compared to the controls. The differences
between the infected groups with and without immunomodulation was not significant (P>0.05). Albumin
globulin ratio decreased significantly (P<0.05) in the infected group with and without immunomodulation
when compared to the controls but the difference was not significant (P>0.05) between the infected groups
with and without immunomodulation. Generally, levamisole administration did not alter the course of the
infection in Yankasa sheep when compared to the infected group without immunomodulation. The
experimental period lasted six weeks.
An epidemiological survey of animal trypanosomosis was conducted in some communities of Jos East LGA,
Plateau State, Nigeria where 558 peridomestic animals (sheep and goats) were bled for both parasitological
and haematological analysis. The screening for the presence of trypanosomes using haematocrit
centrifugation technique (HCT), thin and thick films revealed 51 (9.13978%) were found positive for
trypanosomes. Out of this 36 (6.452%) infected with T. vivax while 15 (2.688%) were found to be infected
with T. brucei. The PCV values were significantly higher in non-infected small ruminants.
A mouse model of Trypanosoma brucei rhodesiense that can be used in pathogenesis and drug studies for
Human African Trypanosomosis (HAT) has so far not been developed. In an attempt to develop such a
model, a study was undertaken to determine the clinical and pathological changes in mice infected with stock
of T. b. rhodesiense (KETRI 2357) and its clone (KETRI 3741). The infections resulted in a mean prepatent
period of 3 (range 3-4) days for KETRI 2537 and 4 (range 3-5) days for KETRI 3741. The first wave of
parasitaemia for both isolates reached peak (antilog 8.7) between 6-8 DPI and was followed by secondary
latency. Thereafter, the parasitaemia increased and remained high, with slight fluctuations. The mean
survival period was 36 (range: 7-45) and 50 (18-82) days for the mice infected with KETRI 2537 and KETRI
3741 respectively. At post mortem, the spleens were enlarged and there was generalized congestion in most
organs. Histopathological changes were more severe in the parent stock compared to its clone.
Meningoencephalitis was observed in mice infected with KETRI 3741 that survived up to 77 days. These
studies demonstrate the development of late stage disease in mice infected with T. b. rhodesiense, with
potential for use as a model of sleeping sickness.
Four hundred thirty two cattle in 9 farms in the Coast and Dar Es Salaam regions of Tanzania were bled at
different periods from March 2006 to January 2007 and specimens prepared for parasitological (buffy coat
technique - BCT, blood slide examination) and serological (Antigen, Antibody, PCR ELISAs and LAMP
Test) screening for presence of trypanosomes. Alongside this, 1.0 ml of EDTA blood of test animals with
packed cell volume (PCV) values less than 25 was inoculated into 20 g mouse for possible detection of
trypanosomes in low parasitaemic infections; were followed-up for 60 days. Four cattle were detected
positive for pathogenic trypanosomes, notably Trypanosoma vivax in three cattle by blood slide examination
and BCT, and T. congolense (one case) by mouse inoculation. Serological screening is not yet completed.
90.3% of animals sampled had PCV values above 25, while 42 cattle (9.7%) had PCV values below 25. Low
PCV values in adult cattle in trypanosomosis-endemic areas suggest presence of trypanosome infections.
Subsequent trypanocidal drug treatment of five parasitologically negative cattle with PCV of 15, 16, 18, 20
and 22 resulted into improved PCV values of ≥25 ≤27 by Day 30 after treatment with diminazene aceturate 7.0mg per kg body weight. Mouse inoculation was discriminately done on blood of parasitologically
negative cattle with PCV values below 25. One pair of mice became positive for T. congolense on Day 43
and 47 of inoculation. Although results from more sensitive diagnostic tests are not yet available, the
individual parasitological tests (blood slide, BCT, mouse inoculation) and trypanocidal drug treatment of low
PCV-BCT-negative adult cattle have shown complementarities to one another; each option has place in
perfecting trypanosomosis diagnosis for an improved control of the disease.