An outbreak of measles that began with a patient in Philadelphia’s top children’s hospital has already sickened up to six patients — with health officials fearing more could be infected.
Three unvaccinated pediatric patients at the Children’s Hospital of Philadelphia (CHOP), as well as an unvaccinated parent, tested positive for the highly infectious virus after an infected infant admitted to the hospital spread the disease to two other hospitalized children.
Additionally, after a patient ignored quarantine orders and attended daycare last month, at least two other patients are also being monitored for suspected infections.
Experts said people catching the disease are not vaccinated against measles, adding the risk to the vaccinated is low.
Unvaccinated people are being urged to get the measles shot, which is more than 97 percent effective against infections with the virus.
Measles is a highly infectious disease that is fatal in up to 15 percent of people that it infects.
Three children and a parent at Children’s Hospital of Philadelphia (pictured) have tested positive for measles. It took two days to diagnose the initial patient, by which time the virus had spread to two others
‘We are seeing cases of measles that have spread to vulnerable individuals, including young children,’ said city Health Commissioner Dr Cheryl Bettigole.
‘[This is] due to people declining vaccination and also failing to adhere to quarantine recommendations.’
Measles is one of the most infectious diseases on record, triggering infections through tiny airborne droplets or via contact with contaminated surfaces.
Patients experience flu-like symptoms in the early stages before a characteristic rash appears, through which the disease is normally diagnosed.
The illness is particularly dangerous for children under five years old, pregnant women and those with weakened immune systems.
The outbreak was triggered when a child with flu-like symptoms who had recently returned from a country where measles is common was admitted to the CHOP late last month, local reports say.
It took two days for the hallmark rash to emerge, which then led to a measles diagnosis — by which time two patients in adjacent rooms had been infected.
For the 2022-2023 school year three percent of kindergartners had a vaccine exemption from one or more required vaccines. This is an increase from 2.6 percent during the 2021-2022 school year and the highest the US has ever recorded
The above map shows the state by state rates of vaccination exemptions for the 2022-2023 school year, highlighting the top five states with the highest percentages of exemptions
The additional cases included a child who was too young to be vaccinated and one whose parents refused to get their child vaccinated.
One of the parents of the unvaccinated child later also tested positive for the virus.
CHOP officials say the patients have been placed into quarantine for at least 21 days until their symptoms resolve, making it ‘absolutely safe’ for people needing to visit the hospital.
Philadelphia health officials are following up with people who may have been exposed after visiting four hospitals in the city — CHOP, St Christopher’s Hospital for Children, Nazareth Hospital and Jefferson Health.
They are also calling parents whose children attended Multicultural Education Station day care in Philadelphia between December 20 and 21.
Measles was once widespread in the United States, but the roll out of vaccines led to the disease being declared eradicated in the US in 2000.
About 1,200 cases of measles are now diagnosed in the US every year — often linked to international travel to countries where measles is still endemic.
Two doses of the vaccine against the disease — dubbed the measles mumps and rubella (MMR) vaccine — are 97 percent effective against an infection with the virus.
Patients are offered the first dose between the ages of 12 to 15 months, with the second administered at least 28 days later.
Adults can also get the vaccine, and are offered two doses spread apart by at least 28 days.
Dr Bettigole added: ‘Children under 12 months and adults who are immunocompromised remain vulnerable to measles but are generally protected because of the wall of immunity created by high community vaccination levels.
‘If you have not been vaccinated against measles or have not vaccinated your children who are 12 months of age or older, please reach out to your healthcare provider to do so immediately.
‘If you or your child has been exposed to measles, please follow public health guidance to avoid exposing additional children.’
The Centers for Disease Control and Prevention (CDC) has warned over falling vaccination rates, saying more than a quarter of a million unvaccinated kindergartners entered schools last year.
Data showed seven percent of children were not up to date on their vaccines, above the target level of five percent or lower.
At the same time, the share of children who are ‘exempt’ from having their school vaccinations is continuing to rise — hitting a record high.
Experts say anti-vaccine sentiment fueled by the Covid pandemic is triggering the rise in people avoiding shots, as well as vaccine fatigue.
There was also an outbreak in central Ohio in February last year which led to 85 cases, mostly among children who were not fully vaccinated.
And in October last year health authorities in Idaho were also reporting cases of the disease.
