June 1, 2000
by R.A. Clappison, DDS, FRCD(C)
From OSAP Monthly Focus # 1. 1999*
COMMENDATION TO THE PROFESSION
The dental profession should be proud of the progress initiated in infection control conduct and guidelines in procedures such as hepatitis B vaccination, routine gloving, heat sterilization and monitoring, and universal precautions. “Healthcare workers and their patients have never been better protected from occupational pathogens.”
AIDS AND HIV: STATS
Between 1996 and 1998 AIDS incidence decreased 18% whereas from 1997 to 1998 the incidence decreased 11% indicating that there is a slowdown in the decline in incidence.
In blood testing nucleic-acid testing (NAT) can detect minute amounts of viral genes before a blood donor’s body identifies the infection. Therefore, in the case of HIV, the time required to identify the virus is reduced from 16 to 5-10 days.
Urine samples can be an accurate test for HIV-1. The study was undertaken at Johns Hopkins School of Public Health and involved 222 adults from age 15-19.
AIDS vaccine development is progressing. Clinical trials are being performed and involve research and development by firms such as Pasteur Merieux (Rhone Poulenc), Merck, Wyeth-Ayerst and VaxGen (AIDSvax). There are about 40 experimental HIV vaccines being tested worldwide. AIDSvax has advanced the farthest. A common method is to place HIV genes in canarypox where it replicates the HIV protein and grants the host immunity.
Because of the use of protease inhibitors some of the most common diseases associated with HIV-infected patients, such as hairy leukoplakia and oral candidiasis, are declining whereas the incidence of oral warts is on the increase.
HEPATITIS C VIRUS
This virus is carried by approximately 3.9 million residents of the USA. The FDA has approved the RIBA HCV 3.0 test for the hepatitis C virus. [Chiron Corporation]. This test is claimed to be more accurate and should assist blood banks in tracking the presence of the hepatitis C virus. The American Red Cross has adopted the NAT test to detect transfusion transmitted viral infections such as HCV and HIV.
Because of the presence of Creutzfeldt-Jacob Disease (CJD) in Great Britain the FDA has recommended that American travellers who resided in Great Britain for over six months during the years 1980 and 1996 be barred from donating blood. Between 1980-1996 23% of American blood donors travelled to Great Britain according to an American Red Cross study. Concern has heightened because of a new variant of CJD (nvCJD) which is connected to younger people who consumed infected beef. The FDA panel is concerned that a human brain disease related to bovine spongiform encephalopathy (mad cow disease) could be spread through blood.
The MMWR (Morbidity and Mortality Weekly Report, August 27, 1999) reported an 8% decrease in active TB disease through 1998. There is much concern about the increase in foreign-born cases from 27% to 42% in 1998. Multi-drug resistant TB (MDRTB) is still a major concern because of the poor response to treatment. Forty-five states reported cases between 1993 and 1998.
SmithKline Beacham has developed a new vaccine (LYMEris) for Lyme Disease and it has been approved by the FDA and is a three-shot series of vaccinations.
Roswell Park Cancer Institute and Cornell University have initiated clinical trials of a hepatitis B vaccine using a genetically engineered potato as a vehicle. The potato must be eaten raw but does not require refrigeration, which would make it more practical in third-world areas. Researchers are attempting to incorporate the vaccine into various palatable food sources.
Meridian Medical Technologies has received FDA approval for a generic injectable version of acyclovir, a medication for treatment of herpes infections. It is claimed that the drug works more quickly when injected.
Approval has also been given by the FDA for Meridian Diagnostic’s two diagnostic tests for the herpes simplex virus. The company claims the blood tests will differentiate oral from genital herpes.
1.”This resource was reprinted with permission of OSAP. OSAP is a nonprofit organization, which provides information and education on dental infection control and office safety. For more information or membership please call (410) 571-0003, Fax (410) 571-0028, 1-800-298-6727 (USA) or www.osap.org
2.Molinari, John , PhD,” Dental Infection Control at the Year 2000, Accomplishment Recognized
3.Sexually Transmitted Diseases, November 1999 Issue