Challenges of caregivers and needs of children with parents in a Nigerian prison.

Background: Separation of a parent from the family as a result of incarceration has both short-term and long-term effects on the family, even after release from prison. This study is a report of factors and challenges of the family left to adapt to the changed circumstances of separation from parent(s) who are incarcerated. Methods: This was a cross sectional study carried out on 89 caregivers of children whose parents are incarcerated at the Agodi prison, Ibadan who gave informed and written consent to interview their families. Results: Most caregivers had little or no formal education (69.7%) and 67.4% are into petty trading or subsistence farming. A majority of the caregivers reported the need of schooling (85.4%), provision of food (84.3%) and medical care (71.9%) as major challenges, only 25% received any form of support to meet these needs. Twenty-nine (32.6%) respondents reported receiving financial support to provide for the child's feeding. Some caregivers 21 (23.6%), obtained loans to cope with the financial needs of the children while only 3 (3.4%) received support from family or other non-governmental organisations. Conclusion: The caregivers of children of prison inmates face significant challenges in meeting the needs of feeding, health and schooling. Support structures and policies to address these gaps are required.

Rift valley fever virus infection among livestock handlers in Ibadan, Nigeria.

Livestock handlers are occupationally exposed to Rift Valley fever virus (RVFV) because of frequent and longer contact with mosquito vectors, animal blood and other tissues. We determined the seroprevalence of RVF virus infection among livestock handlers in Ibadan, Nigeria. Blood samples were collected from 265 workers in two major livestock markets and a livestock farm. Questionnaires were administered to obtain information on risk factors that may be associated with RVF virus transmission. The blood samples were tested using enzyme-linked immunosorbent assays (ELISA) to detect multispecies anti-RVF virus IgG/IgM and human anti-RVF virus IgM. In total, 14 (5.3%) of the 265 participants tested positive for anti-RVFV IgG. Seropositive individuals were more among livestock keepers (5.6%) than butchers (3.6%). Workers that frequently visited the livestock rearing areas of the northern part of Nigeria had a statistically significant (P = 0.004) higher rate of infection compared to those that did not. Very few (0.8%) of these workers knew about RVF virus while none had been vaccinated against the virus infection. This study indicates that RVF virus continues to circulate sub-clinically in Nigeria, thus the need to educate and vaccinate individuals who are occupationally at risk of infection.

High rate of unrecognized dengue virus infection in parts of the rainforest region of Nigeria.

Outbreaks and sporadic dengue virus infections continue to occur in Africa. Several reports of dengue among travellers returning from some African countries to Europe and North America have raised concerns about the epidemiological situation in Africa. We investigated recent dengue infections in febrile patients during the rainy season in various urban centres in the rainforest region of Nigeria, West Africa. This cross-sectional study was conducted for 8 months in 2014 with study participants from Adeoyo Hospital Yemetu - Ibadan, Nigeria. Plasma were collected from 274 febrile patients residing in 11 Local Government Areas of Oyo State. IgM antibodies were determined using semi-quantitative sandwich ELISA. Data was analyzed using Chi - Square and Fisher's exact test with SPSS 16.0. An overall prevalence of 23.4% dengue virus infection was found among study participants. Highest monthly prevalence of 40% was in April and August. The monthly distribution pattern of dengue virus infection indicates efficient virus transmission. Routine diagnosis will enhance dengue virus surveillance and improve patient care in West Africa.

Prevalence of previously undetected tuberculosis and underlying risk factors for transmission in a prison setting in Ibadan, south-western Nigeria.

People with congregational tendencies such as the prison inmates constitute an important target group in the global efforts towards the control of tuberculosis (TB). The prison setting in most developing countries particularly Nigeria, currently does not have routine diagnostic procedures for TB despite the existing risks that could facilitate disease transmission. We conducted a cross sectional study among the inmates in a major prison in south-western Nigeria for TB by screening their sputum samples using a simple random sampling method coupled with questionnaire interview, on the assumption of sub-clinical pulmonary TB infection. The overall TB prevalence found was 1.2% (2/164). Significant risk factors that could facilitate disease transmission in the prison included lack of BCG immunization (p = 0.017); history of contact with TB patients (p = 0.020); prolonged cough (p = 0.016) and drug abuse (p = 0.019). Our findings of 1.2% undetected pulmonary TB infection among the inmates though low; still reiterate previous observation that the prison setting constitutes a veritable environment for TB transmission and a threat to public health. Efforts are therefore needed to institute routine screening and reduce the risk factors associated with TB transmission among prison inmates in Nigeria.

Hepatitis B virus DNA in patients with HBsAg in south western Nigeria.

There are about 400 million people with chronic hepatitis B virus (HBV) infection worldwide with a potential of adverse sequelae including hepatocellular carcinoma. Recent data have shown that the level of HBV DNA in serum or plasma of an infected person probably reflects more accurately the replicative activity of the virus and therefore may serve as a better maker for management of the infection. This study was designed to determine the rate of detection of HBV DNA in blood samples of patients with HBsAg positive in Nigeria in comparison with the HBe and anti-HBe used widely as serological markers of infectivity. Plasma samples from 105 patients with HBsAg positive were tested for the presence of HBeAg and anti-HBe using a commercial enzyme-linked immunosorbent assay while plasma HBV DNA was quantified using the COBAS Amplicor HBV Monitor assay. Of the 105 HBsAg samples, 17 (16.2%) and 85 (81%) were positive for HBeAg and anti-HBe, respectively, while 8 (7.6%) were negative for both HBeAg and anti-HBe. HBV DNA was detected in 86 (81.9%) of the samples, out of which 15 (18.1%) and 67 (80.7%) were positive for HBeAg and anti-HBe, respectively. HBV DNA was detected in 78.4% of the HBeAg negative samples and in all the eight samples that were negative for both HBeAg and anti-HBe. The implication of these findings in the management of patients with HBV infection is compelling.

Hepatitis B and E viral infections among Nigerian healthcare workers.

BACKGROUND: There is dearth of information on Hepatitis E virus (HEV) infection and its co-infection with HBV among Nigerian healthcare workers (HCWs). Hence, there is the need to determine the rate of HEV infection and its association with HBV among HCWs who are at greater risk of nosocomial infections. METHODOLOGY: Sera from 88 HCWs and 44 non-HCWs healthy adults as controls were tested for the presence of antibody to HEV (anti-HEV). The HCWs were also tested for HBsAg and antibody to Hepatitis B core antigen (anti-HBc) using commercially available ELISA kits. RESULTS: The prevalence of anti-HEV obtained among the HCWs and controls were 43% and 94% respectively (p<0.005) while those of HBsAg and anti-HBc in HCWs were respective 13% and 56%. Overall among HCWs, the prevalence of HBV infection was 65.9%, higher than HEV infection (p<0.005) with only anti-HBc greater among the male participants (p<0.005) while co-infection of HBV with HEV was 27.3%. HEV infection was least among the Paediatricians (18%) and highest among the Surgeons (55%) while HBV infection was similar in all the different occupational groups of HCWs (44-59%) except among the Gynecologists and Obstetricians (80%). CONCLUSION: Infection with HEV is high among Nigerian HCWs but lower than the rate among non-HCWs. It is also co-infected with HBV especially among the different groups of the HCWs and could occur with the diverse clinico-serological patterns of HBV infection.

Biological characterization of Nigerian chicken anaemia virus isolates.

Chicken anaemia virus (CAV) DNA was extracted from thymus, liver and bone marrow samples obtained from broiler and pullet chicken flocks in southwestern Nigeria, which presented with clinical signs and lesions suggestive of both infectious bursal disease and chicken infectious anaemia. While CAV was successfully isolated in MDCC-MSB1 cells from four of the pooled tissue samples, the remaining two samples failed to grow in cells. Monoclonal antibody (MAb) characterization using four MAbs produced against the reference Cuxhaven-1 (Cux-1) CAV isolate showed that Nigerian CAV isolates are antigenically related to each other and to the Cux-1 virus. Pathogenicity studies with the Cux-1 virus and one of the Nigerian isolates (NGR-1) revealed that NGR-1 was more pathogenic that the former. We conclude that although Nigerian CAV isolates are antigenically related to each other, they differ in terms of cell culture growth characteristics and probably pathogenicity. These findings further confirm that CAV exists and can no longer be ignored in poultry disease diagnosis in Nigeria. Cases hitherto diagnosed as IBD may actually be CIA or a co-infection of the two.

Affinity (tropism) of caprine arthritis encephalitis virus for brain cells.

One of the constraints in unraveling the mysteries blurring the advancement of research in the quest to totally put HIV problems under control is getting the appropriate animal model that would truly simulate human cases. This problem is more apparent in studies involving the central nervous system. Consequently, a viable animal model to generate information for the production of drugs and vaccines for the prevention and or control of lentiviral induced dementia in affected host animals is pertinent and vital. In this study, explant cultures prepared from the brain of new-born goat-kid were infected with CaprineArthritis Encephalitis (CAE) virus- a retrovirus affecting goats. The specific brain cell types infected by the (CAE) virus were determined using reverse-transcription polymerase chain reaction (RT-PCR) and transmission electron microscopy (TEM techniques). TEM showed that in 85 - 90% cases, microglia were the cells specifically infected by the virus. Amplification of the genomic sequence of the envelope and the gag genes by RT-PCR confirmed the presence of CAEV proviral DNA in the brain cells of affected animals. No productive infection of the astrocytes was observed. The results of this study showed a lot of similarities in the tropism of CAE virus infection of goat brain cells to that of HIV infection in humans thus suggesting the potential usefulness of the caprine model for the study of HIV neuropathology. The goat model system as a non-primate model therefore could be more adaptable as a simple animal model than primate models with their complexity of anthropological, environmental and safety problems.

Sequence and phylogenetic analysis of chicken anaemia virus obtained from backyard and commercial chickens in Nigeria.

This work reports the first molecular analysis study of chicken anaemia virus (CAV) in backyard chickens in Africa using molecular cloning and sequence analysis to characterize CAV strains obtained from commercial chickens and Nigerian backyard chickens. Partial VP1 gene sequences were determined for three CAVs from commercial chickens and for six CAV variants present in samples from a backyard chicken. Multiple alignment analysis revealed that the 6% and 4% nucleotide diversity obtained respectively for the commercial and backyard chicken strains translated to only 2% amino acid diversity for each breed. Overall, the amino acid composition of Nigerian CAVs was found to be highly conserved. Since the partial VP1 gene sequence of two backyard chicken cloned CAV strains (NGR/CI-8 and NGR/CI-9) were almost identical and evolutionarily closely related to the commercial chicken strains NGR-1, and NGR-4 and NGR-5, respectively, we concluded that CAV infections had crossed the farm boundary.

Tumour markers and hepatitis C virus infection in Nigerian patients with liver diseases.

BACKGROUND: Early diagnosis of hepatocellular carcinoma (HCC) is very important and determination of serum levels of tumour markers in patients with chronic liver diseases could be of immense contribution to their management. METHOD: Forty-two adult Nigerian subjects consisting of 14 healthy subjects (Controls) and 28 patients with primary liver mass (es) and histological diagnoses of liver cirrhosis (LC) +/- chronic active hepatitis (CAH) and hepatocellular carcinoma +/- LC were studied. Their blood samples were assayed for Hepatitis B Surface Antigen (HBsAg), antibodies to HCV (anti-HCV), alkaline phosphatase (AP), Aphafeotoprotein (AFP) and Ferritin. RESULTS: The patients had HCC (10) HCC+LC(4), LC+CAH (2) and LC (12). Serum ferritin> 700ng/ml, AP> 375IU/ml and AFP>200IU/ml were detected in 32%, 11% and 32% of the patients respectively with corresponding specificities of 100%, 86% and 100%. Elevated serum levels of AFP and ferritin were found in patients with HCC +/- LC while raised serum AP occurred in those having PHCC without LC. Only combination of either AFP or ferritin to AP gave significant increase in the diagnostic yield of HCC among the patients than the use of only AR Elevated levels of serum AFP correlated with both HBV and HCV while raised serum levels of ferritin were associated with only with HBV CONCLUSION: Although combination of the tumour markers gave a higher diagnostic yield for HCC among Nigerian patients, serum AFP > 200IU/ml seems the best tumour marker in the diagnosis of PHCC among the patients.

Hepatitis B surface antigen (HbsAg) in blood and genital secretions of patients with sexually transmitted diseases in Ibadan, Nigeria.

A total of 100 patients attending the Special Treatment Clinic of the University Teaching Hospital (UCH), Ibadan between October, 1998 and April, 1999 were studied to detect Hepatitis B surface antigen (HbsAg) in the blood and genital discharges. This was with a view of establishing whether infected persons (positive by blood test) also excrete the antigen, HbsAg, in their genital secretions. Urethral swabs were collected from 63 male patients, while High Vaginal and Endocervical swabs were collected from 37 female patients. Blood samples were collected from all the patients. HbsAg was tested for by Enzyme immunoassay technique with Wellcozyme HbsAg kit. Of the 63 male patients, 10 (15.9%) had HbsAg in the urethral secretion while 22 (34.9%) had it in their blood, 70% of these male patients were within the age range 11-30 years. Of the 37 female patients, 34 (92%) had HbsAg in the Endocervical secretions, 6 (16.2%) of them had HbsAg in their blood. Eighty percent of the female patients with positive HbsAg in the genital secretions were within age range 21-40 years. This study documents that Hepatitis B virus can be transmitted sexually in this environment.

Isolation and preliminary characterization of chicken anemia virus from chickens in Nigeria.

Chicken anemia virus (CAV) was isolated for the first time from the Nigerian chicken population. The virus was recovered from necropsied birds from broiler and pullet flocks that suffered disease outbreaks tentatively diagnosed as infectious bursal disease. A sensitive polymerase chain reaction (PCR) assay detected CAV DNA in tissues of necropsied birds. Restriction endonuclease analysis performed with the 733-bp PCR product and the Cfo I enzyme indicated at least two different CAVs were circulating among the Nigerian chicken population. Four isolates were obtained from pooled liver and thymus tissues using the MDCC-MSB1 cell line. These isolates were found to be antigenically closely related to the Cuxhaven-1 (Cux-1) reference strain of CAV when reacted with four monoclonal antibodies prepared against the Cux-1 virus. One of the isolates (isolate A) induced thymus atrophy, bone marrow aplasia, and low hematocrit values when inoculated into 1-day-old specific-pathogen-free chickens. These findings not only demonstrate that CAV is present in Nigeria, but they also likely represent the first cell culture isolation of the virus in Africa.

Demographic factors in HIV infected patients seen at UCH, Ibadan, Nigeria.

There is a rising rate of Human Immunodeficiency Virus (HIV) infection in Nigeria. Good knowledge of the demographic characteristics of the patients with HIV/AIDS may be of great importance in understanding its epidemiology in Nigeria and could facilitate efforts at curtailing the spread of the infection. The study was planned to determine the demographic factors in Nigerian patients with HIV infection. The study was conducted at the University College Hospital (U.C.H), Ibadan, located in the South West of Nigeria. It was a retrospective study of patients with HIV infection attending the U.C.H. from 1988 to 2002. The data collected from the clinical records of the patients with HIV infection included age, sex, marital status, number of spouses, tribe, occupation, education and their religious affiliation. A total of 460 patients aged 1-76 years with peak at 30-34 years were studied. The male/female ratio was 1.06 and the males were the older group. Traders accounted for 40% with female preponderance while the artisans (19.9%) and the military (2.9%) were mostly males. The patients were of Yoruba (70.6%), Igbo (20.0%) and Hausa (9.1%) races. Among the patients with marital status, majority (71.4%) were married while those separated and widowed accounted for 3.5% and 2.6% respectively. Also, a higher proportion of the female HIV patients were Christians whereas the majority of the males were of Islamic religion. Although, there was a low frequency of records on education, the males had better formal education. In conclusion, the study shows that HIV infection is presently an adult disease affecting the most productive segment of the Nigerian population regardless of the individual occupation, educational status, tribe and religious affiliation. Also, it shows that the infection could be associated with heterosexual intercourse.

Oro-facial lesions and CD4 counts associated with HIV/AIDS in an adult population in Oyo State, Nigeria.

OBJECTIVE: The objective of this study was to define the oro-facial lesions associated with Human Immunodeficiency Virus (HIV)/Acquired Immune Deficiency Syndrome (AIDS) in an adult population in Oyo state, Nigeria and to relate these with the level of immune suppression as measured by the CD4 counts. MATERIALS AND METHOD: The study population consisted of 679 consecutive subjects who were seen at the state-owned blood bank. Information on demography, medical and medication histories were obtained. Oro-facial examinations were carried out according to Greenspan et al [Oral Surg Oral Med Oral Pathol (1992)73:142-144]. HIV sero-prevalence status was determined for all patients. CD4+ T-lymphocyte count was carried out for those sero-positive for HIV and 31 randomly selected HIV-negative subjects. Data were analyzed using the chi-square test, Fisher's exact test, Student's t-test and odds ratio where appropriate. RESULTS: Eighty-one (11.9%) of the entire study sample were confirmed HIV positive. The prevalence of specific oral lesions by HIV sero-status revealed that pseudomembranous oral candidiasis and angular cheilitis occurred significantly and more frequently in HIV-positive subjects (33.3 and 21% respectively) than those who were HIV negative (4.3 and 1.8% respectively, P < 0.05). The mean CD4 count of the HIV-positive subjects was 452 cells mm(-3), s.d. 137, while it was 602 cells mm(-3), s.d. 251, for the HIV negatives. The difference was statistically significant (P = 0.000). Forty-four (66.7%) subjects with CD4 counts <500 cells mm(-3) had oro-facial lesions whereas among those with CD4 counts >500 cells mm(-3) only 22 (33.3%) had oro-facial lesions (OR = 4.57). CONCLUSION: The type of oro-facial lesions most commonly associated with HIV/AIDS in Oyo state, Nigeria, has been shown to be pseudomembranous oral candidiasis. This was followed by angular cheilitis. These lesions, although found in HIV-negative subjects, were in a lower proportion as compared with HIV-positive subjects. Mean CD4 counts were lower in HIV-positive subjects and this was associated with greater prevalence of oro-facial candidiasis and angular cheilitis.

Evaluation of modified short course chemotherapy in active pulmonary tuberculosis patients with human immunodeficiency virus infection in University College Hospital, Ibadan, Nigeria--a preliminary report.

Over the period, 1st October 1999 to 30th April 2002 a clinical trial of the modified short-course chemotherapy (SCC) in newly diagnosed cases of pulmonary tuberculosis with human immunodeficiency virus (HIV) infection in Ibadan, Nigeria was carried out. The modified SCC used was adopted by World Health Organisation (WHO)/International Union against Tuberculosis and Lung Diseases (IUALTD) for developing countries and also by the Nigerian National Tuberculosis and Leprosy Control Programmed (NTLCP). The regimen used consisted of ethambutol (E), isoniazid (H), rifampicin (R) and pyrazinamide (Z) in the intensive phase of 2 months. The continuation phase was 6 months of ethambutol (E) and isoniazid(H), i.e. 2EHRZ/6EH. Sputum conversion was 90% at the second month of treatment and there was no bacteriological relapse after 18 months of follow-up. Side effects were few and consisted mainly of acne vulgaris in 20 (22.5%) of 89 patients during the continuation phase. It is concluded that this modified 8-month chemotherapy regimen adopted by NTLCP is efficacious in treatment of smear positive pulmonary tuberculosis (PTB) patients with background HIV infection.

Prevalence of hepatitis B virus surface antigen (HBsAg) in patients undergoing extraction at the University College Hospital, Ibadan.

Hepatitis B Virus (HBV) infection and its sequelae (liver chirrhosis and hepatic carcinoma) are endemic in Africa. The risk of transmission of the infection during dental treatment is real. This study was carried out to determine the rate of Hepatits B Surface Antigen (HBsAg) as a marker of hepatitis B virus infection in patients undergoing dental extraction in order to highlight the potential risk of nosocomial transmission among the Dental Health Workers (DHW) and their patients. Three hundred (143 males and 157 females) consecutive patients requiring dental extraction who volunteered were enrolled into this study. Their ages ranged from 11 years to 95 years with a mean of 37.2 years (SD = 16.725) and a median of 36 years. The overall HBsAg infection rate was 18.3% (55/300). A higher infection rate (23.1%) occurred among the male patients compared with 14% in females (p = 0.0086). The high rate of HBV infection found among this study population suggests that Dental Surgeons in this environment have a high risk of exposure to hepatitis B virus and should be immunized at the beginning of their professional life. Universal biosafety measures should be observed strictly in all invasive procedures.

Human immuno-deficiency virus (HIV) infection among oral surgery patients at the University College Hospital, Ibadan, Nigeria.

The Human Immuno-deficiency Virus is a World-wide epidemic and evidence abound that the infection is spreading rapidly in sub-Saharan Africa with little or no control. Nosocomial transmission of HIV in the Dental Surgery has been documented. This study was undertaken to determine the prevalence of HIV among dental patients undergoing extraction at the University College Hospital, Ibadan. Three hundred patients requiring dental extraction at the dental clinic, UCH, Ibadan who consented were enrolled for the study. Blood samples from these individuals were tested for the presence of HIV antibodies using commercially available ELISA (Monolisa Sanofi, Pasteur, France). All initially reactive samples were confirmed by a commercial Western immunoblot assay (Bio-Rad Norapath HIV kit). A prevalence of 2.3% (7/300) was obtained among individuals tested for this study. Four (2.8%) of the 143 males and 3 (1.9%) of 157 females were positive for HIV antibodies. All the seropositive patients except one were within the age range 20-39 years and most of them (6 out of 7) do not use condom during intercourse. More than half (57%) of the patients had more than one sexual partner. This study shows that the risk of transmitting HIV to DHCW during treatment is also a potential hazard in this environment. Hence, adequate preventive measure should be observed always.

Hepatitis B and C viral markers in patients with sickle cell disease in Ibadan, Nigeria.

Serum samples from 180 Sickle Cell Disease (SCD) patients attending Medical Out patients (MOP) clinic of the Department of Haematology, UCH, Ibadan, Nigeria were tested for the presence of HbsAg and anti-HCV in their blood samples. The result showed that HBV infection was slightly higher (not significant) than HCV infection among SCD patients (P>0.05). In addition, the result showed that the mean number of transfusion was higher among patients who were sero-positive for both HbsAg (5.0 +/- 6.6) and anti-HCV (4.6 +/- 6.7) when compared to patients who were negative for both viruses (2.7 +/- 3.0 and 2.9 +/- 3.2) for HBsAg and anti-HCV respectively. These observations is an indication that there is an urgent need to screen blood units for hepatitis B and C virus infections prior to transfusion in order to reduce HCV infection among SCD patients in Nigeria. Furthermore, it suggests the need to vaccinate SCD patients against HBV in this environment.

Serum hepatitis C virus and hepatitis B surface antigenaemia in Nigerian patients with acute icteric hepatitis.

Acute hepatitis is common in Nigeria and hepatitis B virus (HBV) infection has been a major aetiological factor. However, the role of Hepatitis C Virus (HCV) infection is yet undetermined. Forty-five consecutive Nigerian patients with Acute Icteric hepatitis (AIH) attending the Medical Clinic of the University College Hospital, Ibadan, Nigeria and 45 healthy adult Nigerians (controls) were studied for evidence of infection with both viruses. Questionnaire on risk procedures which predispose to acquisition of both HBV and HCV infections were administered to the patients. Blood samples were collected from all the subjects and tested for antibody to HCV (Anti-HCV) and Hepatitis B surface Antigen (HBsAg) using the second generation Enzyme Linked Immunoassay (Monolisa -R, Sansofi, Pasteur; France). Anti-HCV was detected in 21(47%) and 17(38%) of the patients and controls respectively. The corresponding prevalences of HBsAg were 38(84%) and 11(24%), p < 0.001. Hepatitis B virus infection was found to occur more than HCV infection in the patients with AIH but similar among the controls. Combined HBV and HCV infection occurred more frequently among the patients (42.1%) than in the control (11%) (; < 0.001). Although there was no significant difference in the HCV infection between the two groups, isolated HCV infection is commoner in the control than in the patients with AIH, (p < 0.001). Similarly, single HCV infection is commoner than lone HBV infection among the control, p < 0.05. In summary, this study shows that while both HBV and HCV infections are common in Nigeria, AIH may be more associated with HBV than HCV in the country.

Antigenic relatedness of selected flaviviruses: study with homologous and heterologous immune mouse ascitic fluids

A relacao antigenica de 9 Flavivirus, febre amarela (YF), Wesselsbron (WSL), Uganda S (UGS), Potiskum (POT), West Nile (WN), Banzi (BAN), Zika (ZK), Dengue tipo 1 (DEN-1) e Dengue tipo 2 (DEN-2), foi avaliada por reacao de inibicao da hemaglutinacao cruzada (cross-HI) e reacao de fixacao do complemento cruzada (Cross-CF) entre cada um dos virus e seu fluido ascitico homologo em camundongos. Medias de titulos foram calculadas usando os titulos heterologos e homologos. Reacoes cruzadas CF revelaram maiores variacoes antigenicas entre virus do que reacoes cruzadas HI. Nao houve variacao antigenica significativa entre virus WSL, POT e YF usando cada um dos metodos. Todavia, diferencas definidas da antigenicidade foram observadas entre eles e os virus UGS, BAN e ZK. Nao existiram diferencas significativas entre UGS, BANe ZK ou entre DEN-1 e DEN-2. A relacao sorologica entre Flavivirus e importante para se estabelecer o diagnostico e a epidemiologia destas infeccoes na Africa