MANILA (2nd UPDATE) — An elementary student in Manila died due to suspected diphtheria, a highly communicable bacterial infection, a school officer said Wednesday.

The Grade 4 student of the Jacinto Zamora Elementary School was wracked with fever last Sept. 13, the last day she attended classes, said school nurse Josefina De Guzman, citing information from the child's mother.

The 10-year-old girl later had rashes and mouth sores, and passed away on Sept. 20, hours after she was clinically diagnosed with diphtheria, added De Guzman in a phone interview with ABS-CBN News.

The Research Institute for Tropical Medicine, she said, is conducting laboratory tests to verify the clinical diagnosis and results may be released in a week.

The Jacinto Zamora Elementary School, which has some 2,300 students, has disinfected its premises, said De Guzman. Those who had close contact with the suspected diphtheria patient were also given prophylactic treatment, she said.

No other student has shown symptoms experienced by their late schoolmate, De Guzman said.

Diphtheria primarily infects the throat and upper airways, and produces a toxin affecting other organs, which may in severe cases, also cause myocarditis or peripheral neuropathy, according to the World Health Organization.

The disease is spread through direct physical contact or from breathing in the aerosolized secretions from coughs or sneezes of infected individuals, it added.

Its symptoms include difficulty in breathing and swallowing, and a membrane covering the throat and sinus, Health Spokesperson and Undersecretary Eric Domingo told radio DZMM.

Last year, the government monitored 183 diphtheria cases, of which 55 were confirmed and 13 led to deaths, according to a Department of Health report.

Unvaccinated children, people with weak immune systems and residents of tightly packed areas are most vulnerable to the disease, said Domingo.

Immunization coverage in the country dropped to 40 percent last year, from an average 70 percent in recent years, partly due to mistrust stoked by a dengue vaccine scandal, authorities earlier said.

In 2016, the Philippines became the first nation to use Dengvaxia, the world's first dengue vaccine, in a trial program involving hundreds of thousands of schoolchildren.

But controversy arose after its French manufacturer Sanofi disclosed a year later that it could worsen symptoms for people not previously infected with the virus. Manila stopped the program and banned the vaccine.

The disclosure sparked a nationwide panic, with some parents alleging the vaccine killed their children, though a government-commissioned investigation found no conclusive proof that it did.

Infants as young as 6 weeks can get vaccinated against diphtheria at health centers nationwide, said Domingo. With a report from Agence France-Presse