1950फोराव, होबथाग्रा मुवायाब्रै टिकाफोरनो ल(गोदोनानि बेराम, धनुस्टंकार बेराम, पारथुससिस, आरो लोनथि बेरनायनि बेरेखा), बे बेरामा 10,000 गथ’फोरनिफ्राय सासेनाव जादोंमोन।
In the 1950s, with an immunization schedule limited to four vaccines (against diphtheria, tetanus, pertussis, and smallpox), 1 in 10,000 children developed this disease.