Socio demographic characteristics of the respondents A total of 365 students took part in the study. Of these, 193(52.9%) were male and 172(47.1%) were female. The age of the respondents ranged from 12 to 23 years, 114(31.2%) aged between 12 to 15 years, 241(66%) aged between 16 to 19 years and 10(2.7%) aged between 20 to 23 years (Table 1).

This study was conducted among secondary school students in Mlimba Division, Tanzania. The purpose of using secondary school students in Mlimba Division was to assess whether these students have good knowledge, attitudes and preventive practices towards STDs. The age category from 16-19 years in this study is in agreement with the characteristics of current student population in secondary schools in Ethiopia 23. Several studies have revealed that sexually transmitted infections are the cause of multiple complications as a result of lack of knowledge about STIs 14. Health seeking behavior depends on knowledge about STIs 15. The proportion of students heard about sexually transmitted infections was 95.9%. This finding was higher than 27% in Udupi Taluk, India 16, 45.4% in Gondar, Ethiopia 17, 70.1% in northern Cape Province, South Africa 18, 79% in Dhaka, Bangladesh 19, 86.6% in Malaysia 20, 89.9% in Brazil 21, 92.4% in Nigeria 12, and less than 98% in Dar es Salaam, Tanzania 22. The variation observed compared to other studies could be due to the differences in methodology, sample size, and operational definition used. The socio-cultural, socio-economic, and behavioral characteristics of the study participants may play a great role in the variation observed.

The three STDs; AIDS, syphilis and gonorrhea were the most known by the participating students 21.6% males and 16.4% females. However, genital warts, chancroid and herpes were poorly known by the participating students 0% males and 0.6% females. The findings in our study could be these are uncommon types of STDs which are neglected by policy makers.

The present study indicates that teachers and mass media were the sources of information on STDs to secondary school students in Mlimba Division. Students who reported teachers were source of information; 19.2% males and 18.6% females while mass media; 16.2% males and 12.9% females. The results in this study are low compared to studies conducted in Ethiopia where teachers and mass media contributed 48.1% and 39.7% respectively 24. The findings indicate that more effort is needed by teachers and mass media in Mlimba Division to educate secondary school students on sexually transmitted diseases.

The findings of this study showed that the prevalence of sexual initiation among secondary school students is 11.8% males and 24.9% females. This finding is lower for males and higher for females comparing to the study conducted in Ethiopia which was 21.5% 25.

The majority of participating students had knowledge that condom protects people from STDs; 52.1% were males and 45.2% were females. This result is higher than a study done in Ethiopia where 39.7% had knowledge that condom protects people from STDs 26. Sexually active students, 3.6% males and 2.5% females used condom during last sexual intercourse. The result in the present study is lower than the study conducted in Ethiopia which showed 54.7% used condom during last sexual intercourse 26. In the present study, participants who responded to have sex with only one partner were 16.7% males and 20.0% females. The result in the present study is inconsistent with the study done in Ethiopia which showed 54.4% had fewer than two sexual partners 27.