In the ongoing measles outbreak in Philadelphia, health officials have reported that a ninth person has tested positive for the highly contagious virus. The outbreak started at the Children's Hospital of Philadelphia last month and subsequently spread to a daycare center on Castor Avenue.

The latest case is the fifth person who contracted measles from the daycare center. It has been noted that an unvaccinated child, who had been exposed to measles while receiving treatment at CHOP, violated quarantine guidelines by attending the daycare center.

The city did not disclose whether the ninth person affected by measles was a child or an adult, and no information regarding hospitalization was provided.

Previous cases included one unvaccinated adult and seven children. During the outbreak, six of the infected individuals required hospitalization for treatment but were later discharged.

As the outbreak continues, authorities in neighboring regions like Delaware's Wilmington and Montgomery counties have issued warnings to local residents about potential measles exposure from individuals who visited healthcare facilities outside of Philadelphia.

In a separate incident, a child in Camden County, New Jersey was diagnosed with measles last week. Authorities have not been able to determine the source of the infection, and there is currently no link established with the Philadelphia outbreak.

Health officials are cautioning individuals who may have been exposed in New Jersey to remain vigilant as symptoms may appear up to two weeks after exposure. Anyone who is unvaccinated or lacks immunity should be attentive to symptoms until February 2.

Measles is highly infectious and can be transmitted through airborne particles or contact with contaminated surfaces. The virus can remain airborne for up to two hours, making it considerably more contagious than COVID-19 by certain measures.

The Centers for Disease Control and Prevention (CDC) emphasizes the importance of vaccination, as even a single dose administered to babies at 12 months old is 93% effective in preventing measles. The efficacy increases to 97% with two doses. Individuals born before 1957 or those who have previously contracted measles are considered immune.

Measles can be particularly dangerous for children under 5, pregnant individuals, and those with weakened immune systems. Severe complications from measles include respiratory failure, brain inflammation, and in rare cases, a progressive decline leading to death.

For individuals with known exposure who are not vaccinated or immune, a quarantine period of 21 days is recommended to prevent further transmission of the virus.

The Philadelphia healthcare authorities are working diligently to contain the outbreak and ensure the safety and well-being of the community.