Bloodborne Pathogens

Question 1

What are the routes of transmission for bloodborne viruses?

Answer 1

Direct contact with infected blood fluids, contaminated needles/syringes/unsterile instruments or direct infection via arthropod vectors

Question 2

What are the three transmission routes for the human immunodeficiency virus? (HIV)

Answer 2

Via blood/blood products, contaminated needles, sexually or perinatally.

Question 3

Describe the progression of HIV to acquired immunodeficiency syndrome (AIDS)

Answer 3

Exposure to HIV, seroconversion, asymptomatic, persistent generalised lymphadenopathy, AIDS related clinical features then AID

Question 4

What are some treatments of HIV

Answer 4

• Nucleoside Reverse Transcriptase Inhibitors (NRTIs)
• Non-nucleoside Reverse Transcriptase Inhibitors (NNRTIs).
• Protease Inhibitors (PIs)
• And anti-retroviral therapy which can be combinations of the treatments above.

Question 5

How can you diagnose HIV?

Answer 5

• HIV-specific antibodies via ELISA or western Blotting.

- NAAT used to detect viral RNA serum and viral load.

Question 6

How can you prevent HIV?

Answer 6

Screening of blood products, needle exchange programmes, anti-retroviral prophylaxis for needlestick injuries.

Question 7

What are the hepatitis B virus (HBV) antigens

Answer 7

• HBsAg (surface antigen).
• HBcAg (core antigen)
• HBeAg (pre-core antigen)

Question 8

What are the ways HBV is transmitted?

Answer 8

• Blood or blood products, contaminated needles, tattoos, piercings or acupuncture.

Question 9

What are the clinical features of HBV

Answer 9

Pre-icteric stage (malaise, anorexia, nausea and tender liver). Icteric Stage (jaundice and dark urine) Can lead to cirrhosis and hepatocellular carcinoma

Question 10

Describe what jaudice is

Answer 10

Yellowish pigmentation in the skin, sclerae and other mucous membranes caused by hyperbilirubemia

Question 11

What is the treatment for HBV

Answer 11

Pegylated Interfeuron Alpha

Question 12

Describe some HBV prevention

Answer 12

HBsAg vaccine, HBV immunoglobin, blood screening, needle exchange programmes and sex ed.

Question 13

Describe the transmission of hepatitis C virus (HCV)

Answer 13

Blood and blood products, tattooing, body piercings and acupuncture, haemodialysis (sexual and vertical transmission uncommon)

Question 14

What are the clinical features of HCV?

Answer 14

Usually asymptomatic but can have; fatigue, nausea, weight loss, cirrhosis and hepatocellular carcinoma (last two more rare)

Question 15

Treatment for HCV? and the screening for HCV?

Answer 15

Pegylated interfeuron alpha. Screening = NAAT preformed on blood samples.

Question 16

What is the cause of malaria?

Answer 16

5 species of plasmodium, the most common is plasmodium falciparum. Female mosquitos inject it into bloodstream so it is a zoonotic disease

Question 17

What are the clinical features of malaria?

Answer 17

Flu-like symptoms but p. falciparum can lead to complications such as cerebral malaria, circulatory shock and hepatitis.

Question 18

Diagnosis of malaria?

Answer 18

At least 3 blood films (thick and thin) and NAAT for detecting drug resistance.

Question 19

Malaria treatment?

Answer 19

Chemotherapy to kill blood stages and combination therapy. Example of an antimalarial is chloroquine

Question 20

Malaria prevention?

Answer 20

Sleep under bed nets, cover exposed skin, use mosquito repellent, prophylaxis and vaccines currently being developed.