Public healthwise, 2011 was a mixed bag for Richmond. Chlamydia was up, gonorrhea was down and newly diagnosed cases of HIV rose from 94 in the previous year to 112.

So says preliminary annual figures released by the Richmond City Health District. There were more than 2,500 total diagnosed cases of chlamydia in Richmond during 2011, according to the report. That’s up from an estimated 2,100 in 2010.

The total number of cases of gonorrhea was cut in half, from a little more than 1,200 in 2010 to an estimated 600 cases last year.

The numbers reflect national trends, says Dr. Danny Avula, deputy director of the district. But the public health community hasn’t determined the reason behind the fluctuating numbers.

One hypothesis for the continued rise of diagnosed cases of chlamydia is that the testing methods have become more sensitive, Avula says. Other explanations could be that government, private and nonprofit health agencies are becoming more aggressive about outreach in underserved communities.

The health district provided treatment services to 5, 915 patients for sexually transmitted infections in 2011, says the department’s recently released annual report. That includes testing in communities that traditionally have less access to health care services.

That means the city’s black and Latino populations. And in Richmond, that means conducting outreach in the poorest communities of the city. Indeed, recent maps compiled by the district reveal that the highest numbers of diagnosed cases of sexually transmitted infections are in the city’s East End and South Side.

Efforts to curtail the numbers continue, Avula says. The health department, in conjunction with other regional groups, recently secured a $1.2 million grant from the Centers for Disease Control to develop community-based methods to reduce sexually transmitted diseases.