CNN  — 

This fall, the health of the nation will depend in large part on vaccines.

Health officials are banking on vaccinations to contain monkeypox and polio before those become standing threats in the United States. They’re counting on updated boosters to restore waning immunity against Covid-19. With influenza expected back in the US this fall, flu shots could be critical to prevent severe illness and keep hospitals from becoming overwhelmed.

While the federal government will facilitate getting these inoculations to states, it will be the 2,820 state and local health departments that will spearhead the work of getting shots into arms, and public health experts say it’s not clear that these offices have enough funding or staff to get the job done.

“I think it’s deeply worrisome,” said Dr. Peggy Hamburg, former health commissioner for New York City and former commissioner of the US Food and Drug Administration. “It’s hard to imagine how state and local health departments can all mobilize, and they desperately do need additional support.”

“I think we have to recognize that this is a very vulnerable time,” said Hamburg, who recently chaired a commission for the nonprofit Commonwealth Fund on how to modernize the nation’s public health system.

After almost three years of contending with vaccine hesitancy, politics and a global pandemic, the nation’s public health workers are frayed and leaving their posts. More than 1 in 4 health department leaders quit their jobs during the pandemic, some after harassment and death threats. Studies are underway to measure how deeply those losses extended to their staff.

Now, these depleted agencies are being asked to tackle new threats like monkeypox without additional funding to handle them.

‘Overwhelmed is an understatement’

Can these agencies pull it off?

“Probably not,” says Caitlin Rivers, an epidemiologist and assistant professor at the Johns Hopkins Center for Health Security in an email to CNN. “Public health is chronically underfunded and understaffed. Substantial capacity was built during the COVID-19 response – for example, contact tracing teams – but many jurisdictions have wound down that infrastructure. Covid money is largely inflexible, so it can’t really be used for other threats like monkeypox.”

The nation’s vaccinators say they are struggling.

“Overwhelmed is an understatement,” said Claire Hannan, executive director of the Association of Immunization Managers.

Hannan said her members have not received any funding to carry out a vaccination campaign against monkeypox. Yet they’ve just been asked the change how the vaccine is given, switching from a more familiar under-the-skin injection to a shallower method that squirts the vaccine between skin layers, something that requires training to do correctly. The hope is that intradermal shots, which require one-fifth of a regular dose, can quickly increase supplies of this hard-to-get vaccine.

As a result, immunization managers are scrambling to find money and staff to order vaccines, manually track inventory, transport shots to the locations where they’re needed, train providers, and collect and send data back to federal health agencies like the US Centers for Disease Control and Prevention.

On top of that, ordering has started for updated boosters to protect against the BA.4 and BA.5 subvarian