On 1 September the San Francisco Department of Public Health released its HIV Epidemiology Annual Report 2015, showing that the number of newly diagnosed HIV infections has continued to fall and people with HIV are being linked to care and achieving viral suppression more quickly. But some notable disparities remain, with African-American men and women, in particular, not benefitting as much as the city's population as a whole.
The new findings indicate that San Francisco is making progress towards achieving the goals of its Getting to Zero initiative: zero new HIV infections, zero deaths due to HIV/AIDS and zero stigma for people living with HIV.
"The overall picture is very good, with San Francisco heading toward zero on every HIV measure," said the city's health director, Barbara Garcia. "However, the data also show significant disparities, affirming our focus on efforts for groups who are not experiencing as much progress. Without improvements for these populations, we as a city will not reach zero."
New HIV diagnoses
New HIV cases have declined in San Francisco over the past decade, with a steeper drop starting in 2012. The latest report, which summarises data through 31 December, shows that this trend continues. The number of newly diagnosed HIV infections fell from 309 in 2014 to 255 in 2015 – the lowest since the start of the epidemic. This 17% decline nearly matches last year's 18% decrease.
Compared with the US as a whole, people newly diagnosed with HIV in San Francisco are more likely to be gay men and to be white. Men who have sex with men account for the largest proportion of newly diagnosed people – 72% (vs 54% nationwide) – while 9% (vs 19%) are women and 2% are transgender, mostly trans women. By race ethnicity, 42% (vs 27% nationwide) are white, 26% (vs 24%) are Latino, 17% (vs 43%) are African American and 12% (vs 2%) are Asian/Pacific Islanders.
Although young people aged 20 to 29 have the highest HIV infection rate nationwide, accounting for 36% of new diagnoses in 2014, newly diagnosed people in San Francisco are a bit older, with 30% (vs 24% nationwide) in the 30 to 39 year age range. In addition, 13% were 18 to 24, 23% were 25 to 29, 22% (vs 19%) were 40 to 49 and 11% (vs 16%) were age 50 or older. No infants or children under age 13 have been diagnosed with HIV in San Francisco since 2005.
The annual report also includes an estimate of HIV incidence or new infections, based on a testing method that can distinguish between recent and long-standing infections. The estimated number of incident infections in San Francisco in 2013 was 487, or 58 per 100,000 persons – considerably higher than the 382 actual diagnosed new infections that year.
The steepening of the decline in new diagnoses coincided with the approval of Truvada (tenofovir/emtricitabine) for pre-exposure prophylaxis, or PrEP. Adoption of PrEP was initially slow, however, and some experts commenting on last year's report thought that it probably had not yet had time to have much effect. But PrEP use has expanded rapidly over the past couple years – a recent informal survey put the number of San Franciscans on PrEP at more than 6000, or roughly 20% of the city's gay and bisexual men – and it may well now be having an impact on new infections.
HIV prevalence and mortality
As deaths have declined thanks to effective treatment, the total number of people living with HIV, or prevalence, in San Francisco has continued to rise, reaching 15,995 in 2015. Nearly three-quarters are gay men, 6% are women and 2% are transgender – proportions that have remained consistent over the past few years.
As a consequence of improved survival, the population of HIV-positive people is ageing: currently 60% are over age 50 and 23% are over 60. Adolescents (age 13 to 17) and young adults (age 18 to 24) account for less than 1% of all people living with HIV in San Francisco, but three-quarters of those are young gay or bisexual men.
The number of deaths due to all causes among HIV-positive people fell from 218 in 2014 to 197 in 2015, about a 10% drop. Last year's annual report said that 177 people with HIV had died in 2014 – making this year's figure look like a possible increase – but the 2014 number has been revised upward to 218 with more compete reporting.
In 2013 (the last year with data available) 39% of deaths among HIV-positive people were due to HIV/AIDS-related causes. Other leading causes of death during the 2010 to 2013 period were non-AIDS cancers (14% of deaths), drug overdoses (10%) and heart diseases (9%).
People diagnosed with HIV between 2006 and 2013 had a median five-year survival probability of 87% after progressing to AIDS. People who inject drugs had the lowest survival probability at 75%, while gay men had the highest at 90%.
The cumulate number of deaths among people with HIV reached 20,987 by the end of 2015 – though not all these deaths were due to HIV- or AIDS-related causes.
Cascade of care
San Francisco continues to outperform the US as a whole in moving people through the HIV continuum of care from testing and diagnosis, to linkage to care, to initiation of antiretroviral therapy (ART), to achieving viral suppression.
Overall, 93% of people thought to be living with HIV are aware that they have the infection. The proportion of people diagnosed late – meaning they progressed to AIDS within three months of an HIV diagnosis – fell to 16% in San Francisco in 2014, compared to 23% nationwide. By the end of 2015 there were 9454 San Francisco residents living with stage 3 HIV infection, or AIDS.
People with HIV are being linked to care sooner after diagnosis. San Francisco's RAPID program aims to get newly diagnosed people on treatment as soon as possible, ideally the same day.
In 2014 (the most recent year for which treatment data are available) 84% of newly diagnosed people were linked to care within one month of HIV diagnosis (up from 72% the previous year) and 91% were connected within three months (up from 82%). Three-quarters achieved undetectable viral load on ART within one year after diagnosis (up from 65%). The median length of time between HIV diagnosis and ART initiation was 21 days and the median time to viral suppression was 88 days.
Newly diagnosed women were less likely than men to be linked to care within a month of diagnosis (64% vs 85%), but they were more likely to be remain in care and to achieve viral suppression within a year (79% vs 74%).
Looking at all people living with HIV, viral suppression rates were substantially lower than those for newly diagnosed individuals, both overall (65%) and for most subgroups. Young people (54%), people who inject drugs (58%) and homeless people (33%) were least likely to have an undetectable viral load on their most recent test.
Although US HIV treatment guidelines since 2012 have recommended that all people diagnosed with HIV should start ART regardless of CD4 cell count, the report shows that while almost everyone with < 200 or 200-350 cells/mm3 was on treatment, this fell to 92% of those with 351-500 cells/mm3 and just 80% of those with > 500.
The new data reveal that some disparities remain – and in fact may be widening. African-Americans, in particular, have not seen the same advances as the population as a whole, and are the only racial/ethnic group for whom new diagnoses are stable rather than declining. Some have suggested that San Francisco's overall excellent progress in preventing and treating HIV is in part related to its small and dwindling black population.
Black men have the highest rate of HIV infection – 140 per 100,000 people in 2015, compared with 52 among white men and 83 among Latino men. Similarly, black women have the highest infection rate among women, at 31 per 100,000.
African-Americans are also more likely to be diagnosed late (22%), less likely to start treatment within one month after diagnosis (67%) and less likely to achieve viral suppression within a year (53%); furthermore, black men and women with HIV have higher mortality compared with the city population as a whole.
While men who have sex with men have achieved good progress in some areas – including having among the highest five-year survival and likelihood of viral suppression – they also have the highest rates of sexually transmitted infections (STIs). Rectal gonorrhoea and early syphilis have steadily increased over the past five years among both HIV-positive and HV-negative gay men. However, many people at risk are not receiving regular STI screening.
"If the absolute decline in new HIV diagnoses per year were to continue at the same rate, we could expect San Francisco to achieve zero new HIV diagnoses by 2020," the reported authors concluded. "However, disparities by race/ethnicity, age, gender, housing status, and risk group highlight the importance of continuing to focus on disparities and implementing new, effective approaches that specifically address the needs of our most vulnerable populations."
Getting to Zero progress reported at AIDS 2016
A poster presentation at the recent 21st International AIDS Conference (AIDS 2016) in Durban gave an overview and update of San Francisco's Getting to Zero initiative.
The Getting to Zero Consortium, formed in 2013, includes experts and stakeholders from the San Francisco Department of Public Health, the University of California at San Francisco, local AIDS service organisations, private care providers including Kaiser Permanente, city government and community advocates.
Getting to Zero is working to reach its goals using a three-prong strategy of expanded access to PrEP, rapid linkage to care and initiation of antiretroviral treatment, and retention and re-engagement of HIV-positive people in care.
The consortium's PrEP committee worked to get the word out through the media, social networking and PrEP 'ambassadors', and improved access through provider training and 'navigators' who help people figure out how to pay for PrEP. During the last year PrEP delivery sites increased to more than 30 clinics, over 120 providers were trained to deliver PrEP and community surveys of gay and bisexual men found that PrEP use increased from 15% to 22%.
The rapid ART committee expanded the same-day care and treatment protocol to three additional sites. To date more than 100 newly diagnosed people have been enrolled citywide and the average time from HIV diagnosis to viral suppression has fallen to 87 days.
The retention and re-engagement committee has placed care navigators at city clinics with vulnerable patient populations and formed a frontline worker group for training and capacity building. In addition to retaining patients in care, the initiative seeks to identify people who have recently fallen out of care and are not virally suppressed and to prioritise them for re-linkage efforts. After a year, 73% of such patients enrolled in navigation were re-linked to care.
Finally, the Ending Stigma committee is developing a citywide needs assessment to address HIV stigma and attempting to include consistent measures of stigma in community survey.
"Getting to Zero has achieved strong participation and coordination of >200 community advocates, providers, researchers, city employees, and members of the private sector," the consortium concluded in their poster. "Together, we are implementing a strategic set of activities to reduce the number of HIV-related deaths and new infections by 90% within this decade. We are working in particular to reach people of colour and under-served communities."
San Francisco Department of Public Health. HIV Epidemiology Annual Report 2015. September 2016.
San Francisco Getting to Zero Consortium. The Getting to Zero San Francisco consortium: early results. 21st International AIDS Conference, Durban, abstract WEPEE609, 2016.
View the abstract on the conference website.