Many things can affect how your body responds to a symptom and what kind of care you may need. These include:

• Your age. Babies and older adults tend to get sicker quicker.
• Your overall health. If you have a condition such as diabetes, HIV, cancer, or heart disease, you may need to pay closer attention to certain symptoms and seek care sooner.
• Medicines you take. Certain medicines, such as blood thinners (anticoagulants), medicines that suppress the immune system like steroids or chemotherapy, or natural health products can cause symptoms or make them worse.
• Recent health events, such as surgery or injury. These kinds of events can cause symptoms afterwards or make them more serious.
• Your health habits and lifestyle, such as eating and exercise habits, smoking, alcohol or drug use, sexual history, and travel.

Symptoms of infection may include:

• Increased pain, swelling, warmth, or redness in or around the area.
• Red streaks leading from the area.
• Pus draining from the area.
• A fever.

Certain health conditions and medicines weaken the immune system's ability to fight off infection and illness. Some examples in adults are:

• Diseases such as diabetes, cancer, heart disease, and HIV/AIDS.
• Long-term alcohol and drug problems.
• Steroid medicines, which may be used to treat a variety of conditions.
• Chemotherapy and radiation therapy for cancer.
• Other medicines used to treat autoimmune disease.
• Medicines taken after organ transplant.
• Not having a spleen.

Usually found in dirt and soil, tetanus bacteria typically enter the body through a wound. Wounds may include a bite, a cut, a puncture, a burn, a scrape, insect bites, or any injury that may cause broken skin.

You may need a tetanus shot depending on how dirty the wound is and how long it has been since your last shot.

• For a deep or dirty wound that has things like dirt, saliva, or feces in it, you may need a shot if:
  • You haven't had a tetanus shot in the past 5 years.
  • You don't know when your last shot was.
  • You have not received 3 doses of the tetanus vaccine series.
• For a clean wound, you may need a shot if:
  • You have not had a tetanus shot in the past 10 years.
  • You don't know when your last shot was.
  • You have not received 3 doses of the tetanus vaccine series.

If proper technique and clean instruments are not used, there is a chance of getting an infectious disease when you get a tattoo or body piercing.

Symptoms of an infectious illness may include:

• An overall feeling of tiredness and lack of energy.
• Dark urine or light-coloured stool.
• A new yellow tint to the skin or the whites of the eyes (jaundice).
• Muscle or joint pain that lasts a long time.
• Belly pain.
• Fever.
• Nausea and vomiting.

Symptoms of a severe allergic reaction can start within minutes of eating or being exposed to an allergen. While symptoms usually occur within 2 hours, in rare cases the time frame can vary up to several hours after exposure. Do not ignore early symptoms. When a reaction begins, it is important to respond right away.

• Skin: hives, swelling (face, lips, tongue), itching, warmth, redness
• Respiratory (breathing): coughing, wheezing, shortness of breath, chest pain or tightness, throat tightness, hoarse voice, nasal congestion or hay fever-like symptoms (runny, itchy nose and watery eyes, sneezing), trouble swallowing
• Gastrointestinal (stomach): nausea, pain or cramps, vomiting, diarrhea
• Cardiovascular (heart): paler than normal skin colour/blue colour, weak pulse, passing out, dizziness or lightheadedness, shock
• Other: anxiety, sense of doom (the feeling that something bad is about to happen), headache, uterine cramps, metallic taste

A severe reaction can take place without hives, so make sure to look out for all of the signs of an allergic reaction.