Washington DC - The number of measles cases continues to rise in the southern US, as Health Secretary Robert F. Kennedy Jr. casts doubts on vaccines and suggests Vitamin A and cod liver oil to combat the highly contagious disease.

In the two hardest-hit states of Texas and New Mexico, the number of cases has risen to around 300, according to local authorities. With a few exceptions, all those infected had not been vaccinated.

In Texas, measles cases rose to 259, with 34 infected people requiring hospital treatment, local authorities reported. A child died of measles in Texas in February. At that time, there were 124 confirmed measles cases in the state.

The New York Times reported that the outbreak began in late January when two cases were discovered in the rural community of Gaines County on Texas' western border with New Mexico. The virus then spread there, causing one death in that state that has not yet been fully clarified.

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RFK Jr., a known vaccine skeptic, did explain the importance of immunization in several interviews, but also described it as a personal choice.

At the same time, he claimed in an interview on Fox News, that vaccinations have side effects and that there are also deaths.

Vaccination also causes all the diseases that measles causes, he claimed – a statement that is considered false and dangerous by major US health experts. In other interviews, he referred to vitamin A and cod liver oil as cures.

Biology Professor Kirsten Hokeness from Bryant University disagreed with the health secretary on ABC news, saying – as do many other health experts – that the best method of preventing measles is vaccination.

There is no evidence that the other proposed remedies, such as vitamin A, have any effect, Immunology Professor Scott Weaver from the University of Texas said on the same channel. He noted that there used to be practically no measles outbreaks because most people were vaccinated. Recently, however, that's changed.

In Gaines County, where the outbreak began, the vaccination rate is 82%, according to public broadcaster PBS. According to the US health authority CDC, outbreaks can occur if the vaccination rate falls below 95%.

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Measles is one of the most contagious infectious diseases and can be life-threatening in extreme cases. It is transmitted mainly through droplets and aerosols that are emitted when people cough and sneeze.

The virus triggers symptoms in almost all unprotected people. These include fever, cough, and the typical skin rash that spreads all over the body.