Objective:Chlamydia is made of organism responsible for respiratory as well as genital infections with very serious sequelae.In Nigeria there is paucity of information regards relative frequencies of Chlamydia infection of which this study reports in North West zone of Nigeria.Methods:Three hundred and thirty three(333) blood samples were collected from individuals attending various clinics in North West zone of Nigeria and tested for Chlamydia complement fixing antibody.Swabs collected from positive patients were re-tested using the Romanowsky -Giemsa staining technique.Statistical analysis were carried out in epi-info epidemiological software package.Results:From the total of 333 samples collected and tested for Chlamydia complement fixing antibody (CCFA) only 287(86%) were positive.The culture showed that 215(75%) were positive for Chlamydia trachomatis while only 135(47%) were positive for Chlamydia pneumoniae.Seventy one(71) females had symptomatic infection while 31 males were symptomatic.Of the 104 individuals who were asymptomatic 67 were females while 92 were males.Of the 31 symptomatic males were 22 positive to Chlamydia pneumoniae and the symptoms being that of respiratory syndrome while 9 had difficulty urinating.All the symptomatic women had symptoms resembling that of the pelvic inflammatory disease(PID) and vaginal discharge. Age groups 31-35 had the highest positive samples while the extreme ages had the lowest number of positive individuals and also the lowest number of samples.The number of samples as well as the positive results were validated using the epi-info statistical package version 3.4.1.There was no significant difference in the number of samples from both males and females(χ~2=1.360,CI = 99%).Conclusion:A high percentage of positive result as validated by statistical analysis shows that Chlamydia infections are endemic in the population and efforts should be made to screen for the organism to avoid the “ silent epidemics”. Objective: Chlamydia is made of organism responsible for respiratory as well as genital infections with very serious sequelae. In Nigeria there is paucity of information regards relative frequency of Chlamydia infection of which this study reports in North West zone of Nigeria. Methods: Three hundred and thirty three (333) blood samples were collected from individuals attending various clinics in North West zone of Nigeria and tested for Chlamydia proofing antibody. Swabs collected from positive patients were re-tested using the Romanowsky-Giemsa staining technique. Statistical analysis were carried out in epi-info epidemiological software package. Results: From the total of 333 samples collected and tested for Chlamydia complement fixing antibody (CCFA) only 287 (86%) were positive. The culture showed that 215 (75%) were positive for Chlamydia trachomatis while only 135 (47%) were positive for Chlamydia pneumoniae. Seventy one (71) females had symptomatic infection while 31 males were sy mptomatic. Of the 104 individuals who were asymptomatic 67 were females while 92 were males. Of the 31 symptomatic males were 22 positive to Chlamydia pneumoniae and the symptoms being that of respiratory syndrome while 9 had difficulty urinating. All the symptomatic women had symptoms resembling that of the pelvic inflammatory disease (PID) and vaginal discharge. Age groups 31-35 had the highest positive samples while the extreme ages had the lowest number of positive individuals and also the lowest number of samples.The number of samples as well as the positive Results were validated using the epi-info statistical package version 3.4.1. There was no significant difference in the number of samples from both males and females (χ ~ 2 = 1.360, CI = 99%). Conclusion: A high percentage of positive result as validated by statistical analysis shows that Chlamydia infections are endemic in the population and efforts should be made to screen for the organism to avoid the “silent epidemics ”.