More cases of the disease are being reported at airports in Detroit, Newark and Memphis. This is what you should know about measles and how to know if it is protected.

MEMPHIS – Two years after experiencing what was then the largest outbreak of measles in the nation, the Memphis area is once again a focus of efforts to contain the highly contagious virus.

A "little boy" who arrived on Monday from abroad at the Memphis International Airport undergoes treatment in isolation on Friday at Le Bonheur Children's Hospital after being diagnosed with measles, said Dr. Helen Morrow , health officer of the Shelby County Health Department.

About 75 people who may have been exposed to the disease on the plane or in the hospital have been notified and receive "appropriate monitoring and evaluation services," Morrow said.

Measles is a contagious virus that can be prevented through a two-step vaccination process that is normally completed before children enter school. Symptoms begin with fever, runny nose, red eyes and cough, then a rash that extends from the head down the body.

► March 14: Travelers who landed in Detroit, Newark, Memphis appears with measles
► March 9: Cheerleaders from 39 states potentially exposed to mumps [19659014] ► March 8: HIV, syphilis group in adolescents, adults found in Milwaukee [19659011] Most patients suffer from a relatively mild illness, but the virus can trigger complications such as brain inflammation, which can lead to to hospitalization and even death.

The unidentified boy traveled on a flight from Brussels to Newark, N.J., and from there to Memphis. Because the airport terminal was "practically empty" when the Newark night flight arrived, almost every possible exposure risk involved other pbadengers seated two rows in front of or behind the child and people in the hospital, Morrow said. .

"This child arrived late at night to the airport, so we do not have much exposure from that aspect," said Morrow.

► February 27: Officials in New York City issue a measles warning after a tourist is infected
► October 27: Michigan incarcerated for vaccine denial: Do not give my child more vaccines

The child spent several hours waiting for his connecting flight on Monday at Newark Liberty International Airport and the New Jersey Department of Health issued a warning on Wednesday to pbadengers who were in Terminals B and C between 12:45 and 9 pm ET that day due to possible exposure to the virus.

Measles was suspected because the child had a fever and the indicator rash. Patients are contagious from about four days before to four days after the rash appears.

"To the best of my knowledge, the child is doing very well," Morrow said.

► June 28: Yes, the plague does exist, and it is not the only ancient disease that still lurks
► January 2017: Decomposing and discrediting 10 myths of the vaccine

Asked about the place of the residence boy, Morrow said he or she "came from abroad."

In addition to the patient from Memphis, another international traveler who landed in Detroit earlier this month was confirmed with measles, health officials in Michigan said Wednesday.

Immunization is the most effective method to prevent measles. Babies should receive their first measles, mumps and rubella vaccine at 12 and 15 months of age with a second injection, which guarantees full protection before starting school.

► April 2016: Memphis area suffering from measles outbreak
► July 2015: Measles kills first patient in 12 years [19659011] Through February 24, 13 people in seven states: Arkansas, Illinois, Indiana, New York, Oklahoma, Pennsylvania and Texas, were reported to have had measles, according to the Centers for Disease Control and Prevention.

In the spring of 2016, Shelby County experienced a measles outbreak that sickened seven people, all of whom recovered. Local patients accounted for 8% of the 86 cases of measles reported throughout the country that year.

The Shelby County Health Department was never able to establish how the disease arrived in the county to trigger the outbreak.

Follow Tom Charlier on Twitter: @thomasrcharlier

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