These days, death is often at the door. Death by bullet, death by blood.

President Rodrigo Duterte's "drug war" has left thousands dead at the hands of police, but it is also threatening lives in a different way.

Front-line advocates in this city in the central Philippines say the violent anti-drug campaign is pushing users ever further underground, fueling the spread of disease by stopping efforts to get them clean needles.

Those who work with injection drug users say they are being ­harassed, even arrested, while ­trying to make their rounds.

"The police are paranoid, so we are having trouble reaching ­people," said an outreach worker for a community group that distributes clean needles. He gave only his nickname, Panki, for fear of being linked in any way to drugs.

Experts say the health effects of the violent campaign may be felt for years to come.

"Evidence from around the world shows that this kind of policy has a very negative impact on the rate of infection for various diseases, from tuberculosis to hepatitis and HIV," said Agnes Callamard, a human rights expert at Columbia University who serves as the United Nations' special rapporteur on extrajudicial, summary or arbitrary executions. "There will be secondary deaths that will be very difficult to monitor and quantify."

It is too soon to map out exactly how the drug war will affect the health of Filipinos. With drug use demonized and police acting with impunity, some drug users stay away from support and testing services out of fear, making it tough to track infection rates.

But the Philippines has the ­fastest-growing HIV infection rate in the Asia-Pacific region. A recent UNAIDS study found that HIV cases more than doubled ­between 2010 and 2016, from 4,300 to 10,500.

In Cebu City, roughly 50 percent of the city's injection drug users are living with HIV, according to local authorities.

What is happening here provides early, anecdotal evidence that Duterte's drug crackdown is hindering, rather than helping, efforts to keep people healthy.

Ilya Tac-an, head of the city's HIV detection program, has tracked injection drug use and infection rates since the early 1990s, well before Duterte's rise to power, and has seen firsthand, over decades, how shifting attitudes about drug use and needle programs influence infection rates.

Community groups in Cebu City have long provided clean ­needles, sometimes with support from local authorities, sometimes against their wishes.

When nongovernmental organizations are able to distribute clean needles, rates of illness hold steady, Tac-an said. When the government restricts the distribution of clean needles, more people are infected with hepatitis and HIV.

In 2009, for instance, community groups were asked to shut down their long-running needle exchange program, and the city passed rules limiting the sale of needles without prescriptions. The next year, HIV cases among drug users in Cebu jumped from less than 1 percent to 53 percent, Tac-an said.

In the years since, grass-roots groups have found ways to operate. Now, under Duterte, they are under threat again and fear another spike in new infections.

Those who can afford to buy needles on the black market do so. Those who cannot afford it either get them on the sly, or, when that fails, use a "service needle," which is typically shared five or six times.

"Users support clean-needle programs, but if distribution stops, they will go back to sharing," Tac-an said.

And in the midst of Duterte's "war," needle distribution has been curtailed.

People familiar with Cebu City's drug trade say the local drug of choice, a mix of Nubain and methamphetamine known as a "milkshake," is still widely available and affordable; safe needles, increasingly, are not.

Outreach workers who deliver needles report being stopped by police for "looking" like a person who injects drugs.

"The police are harassing each person with needle marks. If you have needles, you can get arrested," said a second outreach worker, who was too frightened to give his name for fear of being put on a drug watchlist.

When people who inject drugs are jailed, they are often able to continue using drugs behind bars but lose the ability to obtain clean needles.

Panki said he worries constantly about being caught with needles and then being placed on a drug watch and targeted by police. But he will continue to distribute because he understands the stakes.

"If we stop, our peers die," he said.

Kimberly dela Cruz contributed to this report.

Read more:

The death of a Philippine teen was supposed to be a turning point for Duterte. But kids keep getting killed.

Philippines’s Catholic Church sounds alarm amid Duterte’s deadly anti-drug crackdown

Philippine police use chaos of Duterte’s drug war to extort families in distress

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