Antimicrobials – antivirals
John Steele and Jenny Taylor
Key Topics
- • Herpesvirus infections
- • Human immunodeficiency virus (HIV)
- • Implications for dentistry
Learning Objectives
- • To be familiar with the drug treatment for herpes simplex infections
- • To be aware of the potential oral side effects of highly active anti-retroviral therapy (HAART).
Introduction
There are many viruses that are pathogenic to the human body. These range from mild self-limiting infections in an immunocompetent individual – for example common cold – to potentially life-threatening/life-changing infections such as HIV, Ebola virus disease (EVD) and Zika virus disease.
This chapter will provide a concise summary of those viral infections that have drug treatment available as shown in Table 7.1 and then implications for dentists/dental care professionals will be discussed.
Table 7.1 Viral infections
Hepatitis (viral) |
Human Herpesvirus (HHV) infections |
Human Immunodeficieny Virus (HIV) |
Influenza |
Respiratory syncytial virus (RSV) |
There are many other viruses that can affect the oral cavity and associated structures including Coxsackie viruses (hand, foot and mouth disease, herpangina), human papilloma virus (HPV), measles and paramyxovirus (mumps). These will not be discussed here as there are no specific therapeutic agents available although imiquimod is sometimes used off-label to treat oral warts. There are vaccines now available to prevent HPV infection but they will not be discussed in this chapter.
Viral infections can cause non-specific systemic symptoms such as malaise and fever. General supportive advice is recommended such as fluids, rest and regular anti-pyrexial therapies (paracetamol or ibuprofen).
Hepatitis (viral)
The most common types of viral hepatitis are hepatitis A, hepatitis B (HBV) and hepatitis C (HCV). There are two others identified namely hepatitis D and hepatitis E.
This group of viruses essentially cause inflammation of the liver and can have other longer-term sequelae such as liver cirrhosis and the development of hepatocellular carcinoma (HBV & HCV). HBV and HCV are acquired through contact with infected blood or with bodily fluids (semen and vaginal) through unprotected sex. Antiviral medication is available for HBV and HCV and is discussed below.
Hepatitis B drug treatment
Drugs used in the treatment of HBV include adefovir, entecavir and telbivudine, peginterferon alfa-2a, and tenofovir disoproxil.
For specific Hepatitis B antiviral treatment guidance please see https://www.nice.org.uk/guidance/cg165 from the National Institute for Health and Care Excellence (NICE).
Hepatitis C drug treatment
Anti-viral drugs used in the treatment of HCV include boceprevir, sofosbuvir and telaprevir. NICE has also recently recommended, in draft guidance, newer treatment options including daclatasvir, ledipasvir-sofosbuvir, ombitasvir-paritaprevir-ritonavir with or without dasabuvir (https://www.nice.org.uk/news/press-and-media/nice-recommends-new-treatment-options-for-hepatitis-c).
NICE has paused the guidance for HCV treatment at present so that the newer drugs can be properly evaluated.
Herpesvirus infections
There are eight identified viruses in the human herpesvirus (HHV) group, which are summarized in Table 7.2.
Table 7.2 Viruses in the human herpesvirus (HHV) group
HHV subtype | Also known as | Clinical disease |
HHV-1 | Herpes Simplex Virus 1 (HSV1) | Primary herpetic gingivostomatitis Herpes labialis Genital herpes |
HHV-2 | Herpes Simplex Virus 2 (HSV2) | Genital/oral herpes |
HHV-3 | Varicella-Zoster Virus (VZV) | Chicken pox Shingles |
HHV-4 | Epstein-Barr Virus | Infectious mononucleosis Hairy leukoplakia Nasopharyngeal carcinoma Burkitt’s lymphoma Lymphoproliferative disease |
HHV-5 | Cytomegalovirus (CMV) | CMV infection |
HHV-6 | Roseola infantum (‘sixth disease’) Pityriasis rosea |
|
HHV-7 |