It was not immediately clear who carried out the shootings, a provincial government official said.
Two suspects have been arrested in connection with the incidents, police said.
The threat to heath care workers
The UN mission to Afghanistan warned last year that health workers were increasingly at risk.
In May 2020, gunmen attacked the maternity ward of a hospital in Kabul, killing 24 people.
Those administering the polio vaccine will often be accompanied by security due to the persistent threats.
“The fear instilled during Taliban rule, where pro-polio leaders got killed remains a key concern today, and most successors are still afraid and not motivated to endorse polio vaccination,” according to UNICEF.
The vaccination drive has fallen victim to conspiracy theories. Such theories include that the polio vaccine is used to sterlize Muslims, or that some ingredients in the drops derive from pigs, forbidden to Muslims.
The threat of polio
Polio is a disabling and life-threatening virus that spreads from person to person and can infect the spinal cord.
Afghanistan and Pakistan are the only countries where polio is still endemic. Roughly 3 million Afghan children were unable to access a polio vaccine during the past three years due to Taliban militants preventing door-to-door campaigns, according to the Health Ministry.
Afghanistan, in cooperation with UNICEF, started a five-day anti-polio campaign aimed at vaccinating 9.6 million children in 32 of the country’s 34 provinces, on Monday.