Chickenpox nearly wiped out in the US—despite the best efforts of snake oil salesmen and anti-vaxxers

A once-familiar childhood illness is disappearing as doctors recommend a second dose of the vaccine against chickenpox.

States that report vaccination data to the Centers for Disease Control showed an 85-percent drop in cases of the highly infectious disease since 2006, when doctors began routinely recommending a second dose of the vaccine for the varicella-zoster virus, which causes chickenpox, reported Health Day.

The drop was most noticeable among children ages 5 to 14 years old, according to a new CDC report.

Chickenpox -- which causes an itch, blistery rash -- once afflicted an average of 4 million Americans a year as recently as the early 1990s.

About 13,500 patients were hospitalized with the virus, which caused 100 to 150 deaths a year.

The CDC credits vaccination with preventing more than 3.5 million cases of chickenpox each year, as well as 9,000 hospitalizations and 100 deaths.

A single-dose vaccine was introduced in 1996, which led to a 90-percent decline over the next 10 years, but doctors began recommending a second dose after continued outbreaks.

Even in patients whose vaccinations fail to produce immunization, their chickenpox cases are milder than in those who have not had the vaccination.

Despite the success rates, anti-vaxxers continue to promote bogus claims that vaccines are unnecessary or even unsafe, and doctors are reporting that more Americans agree.

A recent survey found that about 87 percent of pediatricians had encountered vaccine refusals, up from 75 percent in 2006, and three-fourths of those parents said they believed vaccinations were unnecessary for diseases eradicated through widespread immunization.

Another survey found that one in 10 Americans — especially those under 30 — actually believed vaccines were unsafe.