Why infection prevention matters at work

Every workplace is shared air, shared surfaces and shared people. A cold that passes around an office, a norovirus outbreak that closes a long-term care home, a needlestick in a dental clinic, a tattoo artist exposed to blood, a custodian who handles a contaminated mop, a paramedic who treats a patient with measles: all of these are infection hazards at work. Some are minor nuisances. Others can cause lifelong illness or death. Almost all of them can be reduced with the same small set of habits, controls and plans.

Infection prevention and control (often shortened to IPAC in Canada and IPC elsewhere) is the set of practices that stop germs from moving from where they are to where they can cause harm. In hospitals it is a profession of its own, with trained infection control practitioners, surveillance systems and committees. In most other workplaces it is part of the ordinary occupational health and safety program: a hazard to identify, assess and control like any other.

This course is written for workers, supervisors, safety committee members and owners in a wide range of workplaces: health care and long-term care, dental and medical offices, personal service settings such as tattoo, piercing and aesthetics studios, schools and child care, laboratories, cleaning and custodial services, first responders, offices and travel-heavy jobs. It is awareness training. It does not certify anyone as an infection preventionist; in the United States and Canada that credential is the CIC, awarded by the Certification Board of Infection Control and Epidemiology, and it requires years of work in the field. Anyone with symptoms, an exposure or a question about their own health should contact their health care provider, their workplace occupational health service or their local health department.

Infections at work are common and costly

Respiratory infections are the most common reason people miss work for illness. Seasonal influenza alone causes millions of lost workdays each winter in North America, and colds, COVID-19 and other respiratory viruses add many more. When workers come to work sick, which many do because of pressure, lost pay or staffing gaps, they spread illness to co-workers, customers and patients, and their own work slows down. Economists call this presenteeism, and studies suggest it can cost employers as much as absenteeism.

In health care the stakes are higher. Infections that patients pick up while receiving care, called health care-associated infections, affect a significant share of hospital patients and kill thousands of people each year in Canada and tens of thousands in the United States. Health care workers are both at risk and a possible route of spread. Long-term care homes, where residents are frail and live close together, were devastated by COVID-19 in 2020 and 2021, and the lessons from that period shape much of today's guidance.

Other sectors have their own patterns. Child care centers and schools see waves of gastrointestinal illness and respiratory viruses. Laboratories handle infectious materials on purpose. Personal service workers pierce skin with needles every day. Cleaners and waste handlers meet sharps and body fluids that someone else failed to dispose of properly. Police, firefighters and paramedics deal with blood and body fluids in uncontrolled settings. Traveling workers may meet diseases that are rare at home.

Recent reminders

The last few years have kept infection prevention in the news. COVID-19 showed how fast a new respiratory virus can disrupt every workplace, and how much ventilation, staying home when sick and vaccination matter. Measles returned in force: the United States confirmed more than 2,200 cases in 2025, and 2026 passed that total by July, the highest since elimination was declared in 2000, with experts expecting the country to lose its elimination status; Canada lost its own status in November 2025. Avian influenza H5N1 spread through dairy herds and poultry flocks from 2024, and about 70 people, mostly farm workers, were infected by early 2026, with one death. None of these mean that every workplace is in danger, but they show why workplaces need plans that can be scaled up quickly.

Prevention works

The good news is that infection prevention is one of the best-proven areas of safety. Hand hygiene programs reduce infections in hospitals and absenteeism in schools and offices. Safety-engineered needles, introduced widely around 2000, cut sharps injuries sharply. Hepatitis B vaccination has nearly eliminated occupational hepatitis B among vaccinated health care workers, a disease that once infected thousands of them every year. Better ventilation lowers the concentration of airborne germs. Simple rules such as staying home when sick, cleaning high-touch surfaces and covering coughs work best when the workplace makes them easy to follow.

# How a small absenteeism cut pays for a hand hygiene and stay-home program (illustrative).
staff = 120
avg_daily_cost = 320          # wages plus benefits per worker-day, dollars
sick_days_before = 6.0        # infection-related sick days per worker per year
reduction = 0.15              # 15% fewer infection-related sick days
program_cost = 9500           # sanitizer, signage, training time, per year

days_saved = staff * sick_days_before * reduction
savings = days_saved * avg_daily_cost
print(f"worker-days saved per year: {days_saved:.0f}")
print(f"value of days saved: ${savings:,.0f}")
print(f"net benefit after program cost: ${savings - program_cost:,.0f}")

worker-days saved per year: 108
value of days saved: $34,560
net benefit after program cost: $25,060

The numbers in this example are illustrative, but the pattern is typical. Even modest reductions in illness repay the cost of supplies and training, before counting the harder-to-measure benefits: fewer infections passed to clients or patients, less overtime to cover absent staff and better morale.

The hierarchy of controls applies

Infection hazards are controlled with the same hierarchy used for chemical or physical hazards, as introduced in HSE-103. The most effective controls remove or reduce the hazard at its source; the least effective depend on each person doing the right thing every time.

In health care, some of these are organized into routine practices (standard precautions in US terms), which apply to everyone at all times, and additional or transmission-based precautions, which add controls for specific infections. Lessons 8 and 10 cover these in detail.

Everyone has a role

Employers provide the program: the risk assessment, the policies, the supplies, the training, the vaccination offers and the response plan. Supervisors make sure the program is followed day to day: that hand hygiene stations are stocked, that sick workers are sent home without penalty, that sharps containers are swapped before they overfill, that new workers are trained. Workers follow the procedures, report exposures and hazards, use the controls provided and look out for each other. Safety committees and representatives review the program, inspect the workplace and recommend improvements. Public health authorities set guidance, investigate outbreaks and may issue orders. Lesson 3 covers the legal duties.

What this course covers

Lesson 2 explains how infections spread, using the chain of infection. Lesson 3 covers the law and responsibilities. Lessons 4 and 5 cover hand hygiene and cleaning and disinfection. Lesson 6 covers respiratory infections, ventilation and outbreaks, and lesson 7 covers vaccination and fitness for work. Lessons 8 and 9 cover bloodborne pathogens, sharps, spills and exposure response. Lesson 10 covers transmission-based precautions and putting on and taking off personal protective equipment. Lesson 11 looks at special settings, and lesson 12 brings everything together in an infection prevention plan.

Some related topics are covered elsewhere. Respirator selection and fit testing are covered in HSE-240. Biosafety levels and laboratory containment are introduced in BIOL-107, lesson 4, and the biology of bacteria and viruses in BIOL-108, lesson 7. Clinical infection control in nursing practice is covered in the nursing courses.

A note on language and stigma

Infection prevention works best when people feel safe reporting symptoms and exposures. Blaming a worker for bringing an infection to work, or treating people with hepatitis, HIV or tuberculosis as dangerous in ordinary contact, discourages reporting and drives illness underground. It can also break human rights and privacy law. Good programs talk about hazards and controls, not about who is to blame, keep medical information confidential and make it easy to do the right thing. The same applies to customers and clients: a respectful screening question at a front desk works better than a sign that treats every visitor as a threat. Throughout this course, examples use plain, neutral language for this reason.