The use of artificial fingernails has become popular and more fashionable in the past. These nails are frequently worn by ladies, health care workers and food handlers. It is estimated that over $265 million is spent every year on acrylic nails and related products and their application in the United States (Shelly et al., 2001). Acrylic is the generic name given to the type of plastic made from a chemical called methacrylate. Some potentially pathogenic organisms such as Staphylococcus aureus, Gram-negative bacilli and yeast are associated with artificial nails. Organisms acquired in this manner tend to be transient and have been repeatedly implicated as vehicles for transmission of nosocomial pathogens and outbreak of foodborne diseases, (Shelly et al., 2001). A recent outbreak in a neonatal intensive care unit was linked to carriage of Pseudomonas aeruginosa on the nails of 2 nurses, one with long artificial nails and the other with long natural nails. Artificial nails facilitate colonization of bacteria on the hands and make hand washing less effective and the use of gloves less practical (Baran, 2002).
On the other hand, foodborne diseases are known to contribute to both human morbidity and mortality as well as health care costs. Besides outbreaks of foodborne disease, health care costs associated with these outbreaks are enormous (Bean et al., 1996; Campbell et al., 1998; USFDA, 2004). These costs include the expenses entailed in controlling the disease, medical treatment costs, business and productivity loses.
This study was undertaken to determine if artificial fingernails could contribute to the transmission of pathogens and in addition lay more emphasis on the restriction of its use by health care workers and food handlers.
This study, which investigated the use of artificial fingernails by both health
care workers and unprofessional food handlers in Port Harcourt, Nigeria, reports
that artificial or long fingernails could serve as vehicle for transmission
of pathogens to foods and causing nosocomial infections on patients. Proper
hand.98 hygiene is the most effective means of preventing the spread of all
infections among hospital patients, health personnel and food personnel. Removal
of pathogens from the hand requires an appropriate cleansing agents, a proper
protocol, compliance and thorough hand washing prior to and after handling a
hospital patient or food. Factors such as type of pathogen, duration of contact
with hands and characteristics of organic material present on hands must be
considered when selecting an appropriate hand washing agent. Additionally, health
care workers and food handlers would be best advised to avoid wearing artificial
nails and keep natural nails trimmed to less than 2 mm beyond the fingertips.
MATERIALS AND METHODS
Study population/subjects: The study populations were all located within Port Harcourt metropolis, Nigeria. The period of study was for one (1) year, (between February, 2006 to February, 2007), with a total of 350 apparently healthy individuals involved; of this number 150 subjects were health care workers, comprising trained nurses, auxiliary nurses, para-medical health care workers and hospital attendants from different private hospitals in Port Harcourt City. The remaining 200 subjects were obtained from various categories of unprofessional food handlers such as food hawkers, snacks hawkers, restaurants and roadside beakers. Females were the only group of people considered in this study because they were artificial and long nails more than the male (i.e., assuming the males were artificial fingernails). Also, women are into food business and nursing more than the men.
Ethical consideration: An informed consent was sought through the medical or managing directors of the various establishments or outfit before sample collection. Educational, family and social background of the employees were equally ascertained and none of the workers or subjects have been known to have any previous hospital acquired infection or case of food poisoning.
Sample collection: Samples were collected during the time of food preparation and service for food handlers, while the health care workers samples were collected during working hours (8 am-4.00 pm). The 10 fingernails of reach individual were wetted with sterile normal saline, using Pasteur pipettes to drop the saline on the end regions of the fingernails. This was to allow the dirt on the fingernails to soften and for easy adherence to the swabs. Sampling the 10 fingers will ensure that no organism was missed. The fingernails were then thoroughly swabbed with a sterile swab stick and the contents transferred into a bijou bottle containing 0.1% peptone water (Oxoid CM509, Oxoid Ltd., Basingstoke, UK). The length of the swab stick was reduced to fit into the bijou bottle. Thereafter, cultures were made by streak plating on surface dried nutrient agar (Oxoid CM3), MacConkey agar (Oxoid CM7) and Deoxycholate agar (DCA) (Oxoid CM163). The culture plates were incubated aerobically at 37°C for 24 h.
Isolation and identification of bacteria: Culture plates showing significant growth (30-300 colonies) were selected and counted. Typical colonies were picked and subcultured onto fresh nutrient agar and MacConkey agar plates for purity checks. Isolates were identified using the method of Harrigan and McCance (1976) and Cheesborough (1987). The values obtained for colony forming units per milliliter (cfu mL-1) and other parameters were calculated using a Chi-square (χ2) test.
RESULTS AND DISCUSSION
A total of 350 fingernails obtained from health care workers and food handlers
were swabbed and studied. Table 1 shows the frequency of microbial
isolates among the subject groups (i.e., Health care providers and food handlers).
Staphylococcus aureus accounted for a higher prevalence of 146 (41.7%)
in both study groups. This is followed by Escherichia coli 26 (7.4%),
while Proteus sp. and Pseudomonas aeruginosa had the least prevalence
of 6 (1.7%) and 5 (1.4%), respectively. Long nails both natural and artificial
can facilitate colonization of bacteria on the hands by making hand washing
less effective and the use of gloves less practical. The longer the nail, the
more likely it is for bacteria to reside under its free edge. Reports from North
America have shown that nurses who wear acrylic fingernails may become colonized
or infected by bacteria and thus become a possible risk to susceptible patients
Also in the routine care of patients, hands of health workers become contaminated.
However, despite the potency of hand cleansing agents used in removal of bacteria
from their hands, health personnel have been incriminated repeatedly as vehicles
for microbial transmission (Schaberg et al., 1996). Similarly, hand
contact with foods represents a mode by which contamination and foodborne outbreaks
may occur (Jack and Marianne, 1999). In this study, Staphylococcus aureus
were more prevalent 146 (41.7%) and this is in contrast to reports obtained
from other studies. Baran (2002) recorded increased carriage of Gram negative
rods such as Pseudomonads (44%) Acinobacter (16%) and Serratia
(37%) from the fingertips of operating rood nurses wearing artificial nails
than from those with natural nails. Also from Oklahoma City, of 439 infants
admitted to the neonatal intensive care unit 46 (11%) acquired Pseudomonas
aeruginosa, 16 (35%) of whom died. This was traced to artificial fingernails
worn by the nurses. Also, Hedderwick et al. (2000) in their research
work isolated more Gram negative bacilli than other pathogens. This research
work recorded a reduced occurrence of Gram negative bacilli with a range of
Esherichia coli 26 (7.4%), Proteus sp. 6 (1.7%) and Pseudomonas
aeruginosa 5 (1.4%), respectively.
|| Frequency of microbial isolation among the subject groups
|Values in parenthesis represents the percentages
|| Influence of nature/length of fingernails on frequency of
microbial isolation on subject groups
|Values in parenthesis represents the percentages. p>0.05
|| Morphological and biochemical characteristics of bacterial
isolates from fingernails of subject groups
|GM+ve = Gram positive, A/G = Acid and Gas, GM-ve = Gram Negative
The type of fingernails and microbial isolation is shows in Table
2. The nature and length of fingernails have an influence in propagation
of microorganisms and this was statistically significant in both health care
workers and food handlers. Artificial nails from health care workers yielded
30 (93.8%) isolates out of 32 samples cultured, long natural fingernails had
44 (84.6%) isolates from 52 samples examined, while short natural nails recorded
41 (62.1%) isolates from 66 samples examined. Conversely, a similar result was
obtained among food handlers. Out of 40 artificial nails examined 39 (97.5%)
yielded a positive result, while 55 (90.2%) isolates was recorded in long natural
nails from 61 samples examined, short natural nails gave 81 (81.8%) positive
cases from 99 samples (Table 2). This figure agrees with the
reports obtained by Hedderwick et al. (2000). During their study 92 out
of the 104 health care workers were assessed for fingernail length and presence
of artificial nails. Those with short or medium length nails have a low risk
of Pseudomonas aeruginosa colonization, whereas those with long natural
or artificial nails had a significant risk.
This study equally confirms the fact that health workers as well as food handlers wearing artificial fingernails had more pathogens isolated from their nails. About 290 (82.9%) of the population (350) under study yielded positive cultures. This high prevalence and frequency in microbial isolation observed in this work could be attributed to social and educational background of subject groups under study. Health care workers mainly comprised of auxiliary nurses and hospital attendants who have not obtained formal education. Similarly food handlers were made up of unprofessional cooks/waiters and waitresses, food/snacks hawkers and roadside restaurants. However, further investigations revealed that government hospitals, health centres, five-star Hotels and fast food centres prohibit the use of acrylic fingernails by staff. This implies that operational policies and standards are already implemented in these areas.
Table 3 shows the biochemical characteristics of bacterial
isolates from fingernails of both health care workers and food handlers. Four
genera of bacteria were isolated from the fingernails of the subject groups.
Among these were Staphylococcus aureus, Escherichia coli, Proteus
sp. and Pseudomonas aeroginosa. A breakdown of the occurrence of
the bacterial flora shows that Staph, aureus and E. coli
occurred in most of the fingernails examined, followed by Proteus sp.
and P. aeroginosa. Staphylococcus aureus, Escherichia coli are
known to be involved in food poisoning cases. Therefore, food handlers should
ensure that their fingernails are trimmed.
The danger in isolating or identifying some recalcitrant pathogens like P. aenigiorosa is that they are resistant to most antibiotics and disinfectants, hence, when transferred to foods or wounds through the longnails of food handlers or health workers, food poisoning may occur and the wound may not heal easily. In the same vein, most of the ready-to-eat foods that are contaminated with Staphylococcus aureus and E. coli that does not require further heat treatment could result to food borne illnesses. (Wachukwu et al., 2002). Therefore, the Hazard Analysis Critical Point (HACCP) should be seriously considered when handling ready to eat foods, since some of them does not require further heat treatment that could kill organisms.
In Nigeria, most women wear artificial nails (particularly young ladies) without knowing the health implications. The present study highlighted different intervention measures that can be used to minimize or eliminate contamination of foods by food handlers or transmission of pathogens to patients by health workers. Implementation and adherence to infection control practices are the keys to preventing the transmission of hospital acquired infections and food poisoning pathogens.
Also, rings and jewelries are thought to harbour food debris, microbial contaminations and food allergens. Therefore, their use should be discouraged in health organizations and food industries.
Finally, the information gathered in this study that artificial fingernails have impact in the transmission of pathogens should be of great importance and concern to the general public, especially those that live around the coastal or riverine areas of the Niger Delta in Nigeria, who use water and bare-hands to wash up after defeacation without adequate hand washing.