Needle stick injuries in the community

Question 1

What pathogens should you worry about with a needle stick injury?
What is their risk of transmission?

Answer 1

Hepatitis B virus - 2 - 40%, depending on viremia
Hepatitis C virus - 3 - 20%, fragile virus
HIV - 0.2 - 0.5 %, fragile virus, susceptible to drying

Question 2

What is the mean age of needle stick injuries in the community?

Answer 2

5-8 years

Question 3

Why is Hepatitis B more likely to be transmitted?

Answer 3

It is a stable virus and can be transmitted by a minute amount of blood. It can survive for up to one week under optimal conditions.

Question 4

What is the post exposure prophylaxis for hepatitis B virus?

Answer 4

Anti-HBV immunogolubin

HBV vaccine - 3 doses

Question 5

Why is the post-exposure prophylaxis for hepatitis C virus?

Answer 5

There is no effective post-exposure prophylaxis.

Question 6

What is the therapy for chronic hepatitis C virus?

Answer 6

Alpha-interferon and ribavirin

Their value in prophylaxis is unknown

Question 7

If there is no prophylaxis, why is it important to determine hep C virus status at the time of needle stick injury?

Answer 7

It is important to determine potential exposure results in transmission in HCV because 50-60% of infected children will have persistent, asymptomatic infection so follow up is essential. These kids may need treatment.

Question 8

What are important considerations regarding the risk of transmitting HIV?

Answer 8

Higher viral inoculum (amount of blood and concentration of virus)
Size of the needle
Depth of penetration
Time between withdrawal of the needle and the needle stick injury - i.e. is the blood fresh

Question 9

What is the HIV post-exposure prophylaxis? How effective is it?

Answer 9

Zidovudine - reduces the risk by 80%

Prophylaxis with combination antiretroviral therapy is presumed to be even more effective, although limited data

Question 10

What would you advise a parent to do over the phone?

Answer 10

Clean the wound thoroughly with soap and water ASAP. Do not squeeze to induce bleeding
Bring the kid to the office to be assessed

Question 11

What would you assess the kid for, in your office?

Do you do any investigations?

Answer 11

Look at the wound: size and depth. Exposure to mucous membranes is also important
Check immunisation status: tetanus and HBV
Document the injury (where, when, type of needle, syringe attached?, visible blood, bleeding post injury)
Investigations: yes - you do baseline HBV, HIV, HCV status

Question 12

Should you test the needle for HIV/HBV/HCV?

Answer 12

Testing needles and syringes for viruses is not indicated. Results are likely to be negative, but a negative result does not rule out the possibility of infection

Question 13

If ha child has not been fully vaccinated against HBV, what do you do?

Answer 13

Test for anti-HBs antibody and HBsAg.

If results are not available:

• give HBIG immediately - really within 48 hrs, but up to 7 days. 0.06ml/kg
• Give HBV (ASAP but up to 7 days)

Results:
Anti-HBs Antibody -ve and HBsAG -ve –> complete vaccine series
Anti-HBs Antibody or HBsAg positive, discontinue vaccine series and arrange FU it HBsAg positive

Question 14

If they have been fully vaccinated for HBV?

Answer 14

Test for anti-HBs antibody. If results not available within 48 hours, give HBV dose x 1

If anti-HBs antibody +ve: no further action

If anti-HBs antibody -ve: test for HBsAg:
HBsAg +ve: arrange follow up
HBsAg -ve: give HBV x 1 and HBIG

Question 15

When do you give HIV prophylaxis? (3)

Answer 15

Antiretroviral prophylaxis should be recommended only in cases of high risk:

1. in which the source is likely to have HIV
2. the incident involved a needle and syringe with visible blood
3. blood may have been injected

Question 16

What do you do if HIV prophylaxis is not indicated?

Answer 16

At baseline HIV.

Repeat anti-HIV antibody at 6 weeks and 3 months

Question 17

What are your options for HIV prophylaxis?

Answer 17

Low risk:
Zidovudine + lamivudine
High risk:
Zidovudine + lamivudine + lopinavir/ritonavir

Question 18

What is the ideal timeframe for starting HIV prophylaxis?

Answer 18

ASAP, within 1-4 hours ideally.

It is not recommended if > 72 hours

Question 19

What do you do if parents are undecided re HIV prophylaxis?

Answer 19

Advise to start it, then can consider stopping it.

Question 20

How long do kids take HIV prophylaxis?

Answer 20

28 days

Question 21

Will a four week course of antiretrovirals have any negative long term consequences re adverse events?

Answer 21

No long term effects

Question 22

What type of follow up do you need to arrange for kids on HIV prophylaxis?

Answer 22

Follow up after 3 days to review adherence and review side effects
Follow up at 4 + 6 weeks with CBC, ALT, AST, BUN, Creatinine

Question 23

What are some side effects of HIV prophylaxis

Answer 23

Zidovudine + lamivudine:
Symptoms: anorexia, N+V, diarrhoea, AP, fatigue and headache.
Asymptomatic: mild neutropenia, anemia, elevated liver enzymes (all resolve after treatment)

Lopinavir/ritonavir: N+V, diarrhoea and AP

Question 24

Why follow up BW do the kids need?

Answer 24

Testing at encounter (baseline)
6 weeks: Anti-HIV antibody
3 months: anti-HIV antibody + anti-HCV antibody
6 months: anti-HIV, anti-HCV and anti-HBs antibody (unless previously positive)

NB if anti-HBs antibody negative at 6 months, retest at 1-2 months after last vaccine

Question 25

What is the vaccine schedule for those that need HBV vaccine?

Answer 25

at encounter, then 1 month and 6 months

If negative anti-HBs antibody 2 months after last vaccine, give a 4th dose