Successful vaccination of cats against Brugia pahangi with larvae attenuated by irradiation with 10 krad cobalt 60

Cats were vaccinated by the inoculation on 10 occasions of approximately 300 larvae of Brugia pahangi which had been irradiated with 10 krad cobalt 60. They were challenged on 3 occasions with normal larvae of either B. pahangior B. patei. The vaccinated cats were resistant to challenge as demonstrated by either longer pre-patent periods or failure to become microfilaraemic and by having fewer third, fourth or adult worms than normal controls. Although the vaccination procedure was unpractically heavy these results lend encouragement to the possibility of developing vaccines against filarial infections.