Needlestick injuries in Italy
Clinical bottom line
In an analysis of almost 20,000 cases of occupational exposure, one in 100 workers with percutaneous exposure to HCV infected blood will be infected, as will one in 500 exposed to HIV infected blood (and with postexposure prophylaxis). These are high rates.
Reference
G Ippolito et al. Surveillance of occupational exposure to bloodborne pathogens in health care workers: the Italian national experience. Eurosurveillance 1999 4: 33-36.
Study
A multicentre prospective study of the risk of transference of HIV and other bloodborne pathogens to healthcare workers following occupational exposure has been ongoing since 1986. Hospitals are enrolled on a voluntary basis. Participating hospitals must actively encourage reporting of exposures, and must have an employee health team.
In 1994 a modified EPINet programme was adopted to record all occupational exposures in greater detail. There are now 41 hospitals taking part, 14 of them teaching hospitals. They have together about 36,000 beds, and employ 62,500 workers.
Results
Occupational exposures
From January 1994 to June 1998 (5.5 years) there were 19,860 occupational exposures, 75% percutaneous and 25% mucocutaneous. Known infected sources were involved in 28% of all exposures: HCV 63%, HBV 13%, HIV 11%, and two or more of these together in 13%.
Employee groups involved are shown in Table 1. One in ten exposures involved personnel in training.
Table 1: Staff involved in occupational exposure
| Exposure per 100 full time equivalents |
||||
| Occupation |
FTE positions |
Percutaneous |
Mucocutaneous |
Total |
| Surgeon | 6534 |
10.1 |
1.9 |
12.1 |
| Nurse | 43897 |
8.4 |
2.6 |
11.0 |
| Midwife | 1002 |
6.6 |
4.7 |
11.3 |
| Housekeeper | 14603 |
4.0 |
0.9 |
4.9 |
| Physician | 12491 |
2.8 |
1.1 |
3.9 |
| Laboratory worker | 6855 |
2.7 |
1.4 |
4.1 |
Devices
Two-thirds of the percutaneous exposures involved needle devices, and other sharps items 30%. There were 10,122 hollow bore needlesticks, and the particular devices involved here are shown in Table 2. Most injuries occurred during or after use, but before disposal of the device.
The Rates per 100,000 devices for each year between 1991 and 1997 is shown in Table 3, which shows that IV catheters and winged steel needles were associated with higher rates of injury than disposable syringes or vacuum tube phlebotomy sets.
Table 2: Proportion of needlesticks from 10,122 hollow bore needles
| Device |
Percent of injuries |
| Disposable syringes | 44 |
| Winged steel needles | 29 |
| Vacuum tube phlebotomy sets | 5 |
| IV catheters | 10 |
| Other devices | 12 |
Table 3: Injury rates by needle device
| Rate per 100,000 devices |
||||
| Year |
Disposable syringe |
Winged steel needle |
Vacuum tube phlebotomy set |
IV catheter |
| 1991 | 4 |
10 |
5 |
14 |
| 1992 | 3 |
14 |
6 |
17 |
| 1993 | 3 |
14 |
3 |
13 |
| 1994 | 3 |
9 |
3 |
12 |
| 1995 | 4 |
12 |
3 |
17 |
| 1996 | 3 |
9 |
3 |
21 |
| 1997 | 3 |
9 |
3 |
16 |
Seroconversion for Hepatitis B
There were 1,155 exposures to HBsAg positive sources, and 158 of 926 (1994-1998) involved susceptible healthcare workers, 117 of whom received active and passive immunoprophylaxis after exposure. There were no seroconversions.
Seroconversion for Hepatitis C
The results for hepatitis C are shown in Table 4. For blood-filled hollow bore needles the seroconversion rate was 0.85% (95% confidence interval 0.4 to 1.5%).
Table 4: Seroconversions for hepatitis C
| Number |
Rate |
|
| Exposure type |
Infected/exposed |
(%, 95% CI) |
| Percutaneous | 12/3076 |
0.4 (0.2 - 0.7) |
| By hollow bore needle | 12/1955 |
0.6 (0.3 - 1.1) |
| - blood filled | 11/1301 |
0.9 (0.4 - 1.5) |
| - non blood filled | 1/631 |
0.2 (0.0 - 0.9) |
| By other sharp object or solid needle | 0/987 |
0 |
| Mucocutaneous contamination | 2/225 |
0.4 (0.0 - 1.3) |
| Non-skin contamination | 0/473 |
0 |
Seroconversion for HIV
The results for HIV are shown in Table 5. For blood-filled hollow bore needles the seroconversion rate was 0.21% (95% confidence interval 0.03 to 0.5%). One worker seroconverted after conjunctival exposure to blood.
There was data on 789 workers given post-exposure prophylaxis with zidovudine monotherapy. More than half reported adverse events, mainly gastrointestinal, and 18% discontinued therapy because of adverse events after a mean of seven days.
There was data on 103 workers given post-exposure prophylaxis with two reverse transcriptor inhibitors and 112 with these plus a protease inhibitor. Adverse events were again common, and 5% and 12% stopped treatment because of adverse events after a mean of 11 and 10 days respectively.
Table 4: Seroconversions for HIV
| Number |
Rate |
|
| Exposure type |
Infected/exposed |
(%, 95% CI) |
| Percutaneous | 3/2125 |
0.14 (0.03 - 0.4) |
| By hollow bore needle | 2/1434 |
0.14 (0.02 - 0.5) |
| - blood filled | 2/962 |
0.21 (0.03 - 0.8) |
| - non blood filled | 0/344 |
0 |
| By other sharp object or solid needle | 1/470 |
0.21 (0.06 - 1.2) |
| Mucocutaneous contamination | 2/468 |
0.43 (0.05 - 1.5) |
| Non-skin contamination | 0/573 |
0 |
Comment
There is a wealth of detailed information in this short study, examining nearly 20,000 occupational exposures. While most exposures resulted from disposable syringes, this was because of the number being used. Winged steel needles and IV catheter sets had the highest rates of injury.
One in 100 workers with percutaneous exposure to HCV infected blood will be infected, as will one in 500 exposed to HIV infected blood (and with postexposure prophylaxis). These are high rates.