According to US health functionaries, a whooping cough outbreak has affected more than 1,500 individuals across the different parts of the country.

State of California has witnessed more than 1,500 reports of pertussis, or whooping cough during the first six months of 2010 as compared to around 300 cases during the same period last year (2009).

Other US states such as Michigan, South Carolina, Ohio and New York have reported a surge in the incidence of whooping cough.

Around seven infants have lost their lives because of whooping cough in 2010 in what is being called the largest eruption during the last 50 years.

The department is urging people, mainly preggies and those who come into contact with babies, to make sure they are immunised for the contagious disease.

Jennifer Liang, an epidemiologist with the US Centre for Disease Control and Prevention stated, "The magnitude of the increase in California is concerning, and that's why we are trying to emphasise the importance of vaccination." (With Inputs from Agencies)