What comes to mind when you hear the word “worms”? Little pink squiggly guys that happily munch on soil? Or the type that can set up shop in your intestines? When we talk about worms in humans, we’re usually describing an infection with a particular type of intestinal worm called a threadworm or pinworm. But there are other types of worms that can infect people and live in their intestines. Here, we’ll explain a bit about these types of worms to help you understand the difference.

Pinworms or threadworms

The most common type of worm infection in New Zealand is caused by threadworms, which are also called pinworms. The scientific name for this type of worm is Vermicularis enterobius. Part of the reason threadworms are so common in New Zealand is because they live in both tropical and temperate climates. Threadworm in kids is much more common than threadworms in adults, but it can affect anyone and is spread very easily between children at school and other family members at home.

So, what are pinworms or threadworms, and what do they look like? Threadworms are small whitish worms that are about 5 to 10 mm long and look a bit like a piece of cotton thread. These worms live in human intestines (your guts), but this part of the infection doesn’t usually cause too many problems. It’s when the females travel out of the intestines to lay their eggs around the anus that most of the problems start. This causes itching around the anus leading to scratching that results in threadworm or pinworm eggs getting all over the hands. Once hands are contaminated, these threadworm eggs can be transferred to mouths, food, and other objects to continue the cycle of infection in the same person or infect other people.

While threadworms are quite common and highly contagious, the good news is that a threadworm infection is generally harmless and is easy to treat. Pinworms in both kids and adults can be treated with a single dose of an over-the-counter medication such as VERMOX.

Hookworms, roundworms, and whipworms

There are a number of other types of worms that can infect humans. These include hookworm, roundworm, and whipworm. These types of worms are much more common in tropical climates and are often associated with poor sanitation or hygiene practices. Luckily for us, these infections are not as common here in New Zealand as they are in other parts of the world because of our more temperate climates and generally high sanitation standards. In New Zealand, they are more likely to be brought back from travellers returning from countries where they are more common.


Infections of hookworms in humans occur mostly when the immature hookworm larvae burrow into unbroken skin that comes into contact with contaminated soil or faeces. Hookworm infection can also occur via ingestion of the larvae. Once the hookworm larvae break in, they travel via blood vessels to the lungs and eventually make their way into the intestines. Here, they attach to the intestinal walls and suck blood from the host before the females lay eggs. The hookworm eggs leave the body in the faeces, which then hatch in soil under the right conditions. Hookworm infections can result in skin irritation where the larvae enter, mild cough or throat irritation when the larvae head to the lungs and stomach, and some stomach or digestive tract issues when they reach the intestines. However, the most serious issue with hookworms in humans is potential blood and nutrient loss when the adult hookworms attach to the intestinal wall. Improved sanitation and hygiene measures can help prevent hookworm infection, as well as wearing protective footwear in areas with contaminated soil.


Roundworms in humans are also spread via soil or water contaminated with human or pig faeces containing roundworm eggs. Infection with this worm can also result from ingestion of larvae in uncooked meat. Once ingested, the roundworm eggs hatch in the intestines where the larvae break through the intestinal wall and travel through blood vessels to the heart and lungs before being swallowed again. Mature roundworms then live in the intestines for a few months before the females lay eggs, which leave the body in the faeces. Most roundworm infections don’t cause symptoms, but sometimes some breathing issues can occur when the larvae are moving around and some intestinal or organ problems can arise when there are adult worms in the intestines.


Whipworm is another intestinal worm that can affect anyone, although children are often at higher risk of becoming infected. Whipworm is transmitted via soil that is contaminated with human faeces that contain whipworm eggs. If this contaminated soil is ingested after coming into contact with food or hands, the eggs hatch in the intestines where worms grow and mature before the females lay eggs. While most whipworm infections don’t cause symptoms, more severe infections can cause unpleasant and sometimes serious digestive tract problems such as diarrhoea. The key to reducing the spread of whipworm is improving sanitary conditions and carefully washing any produce grown in contaminated soil.

So now you’re up to speed about the common and not-so-common worms that can infect humans in New Zealand. If you think you have a worm infection, you should always discuss your symptoms and treatment options with your doctor or pharmacist. As well as providing effective treatment to kill common threadworms with one dose, VERMOX can treat other intestinal worm infections caused by whipworm, roundworm, or hookworm. For directions on how to take VERMOX for these types of worm infections, talk to your doctor.

Frequently asked questions about types of worms


VERMOX kills adult threadworms with one dose. VERMOX can also treat infections with hookworm, roundworm, and whipworm, but you should talk to your doctor or pharmacist before taking VERMOX for these worm infections.


While infection with worms other than threadworm is not common in most of New Zealand, it is possible to become infected with more than one type of worm. If you are uncertain about what type of worm infection you may have, speak with your doctor.


Female threadworms usually lay their eggs during the night, so these thread-like worms are visible on underwear, bed sheets, or around the anus in the morning. Pinworm eggs are pretty tiny but can be picked up from around the anus using a piece of sticky tape. A doctor can look at this tape under the microscope to identify the pinworm eggs and confirm a pinworm infection.


Yes, threadworms and other types of intestinal worms can easily be spread between people via contact with people, objects, or soil contaminated with infective worm eggs.


Some worm infections may not cause any symptoms at all, and when symptoms do occur, they will differ depending on which type of worm is causing the infection and the intensity of the infection. For example, the main symptom of a threadworm infection is itching around the anus.