As an expert in the field of public health and epidemiology, I can provide some insights into the concern about blindness caused by exposure to dog feces. It is important to understand the potential risks and the biological agents that can be transmitted through contact with dog feces.

Firstly, the primary concern when it comes to dog feces is the presence of parasites, particularly the Toxocara canis, a type of roundworm that is common in dogs. These worms can lay eggs in the feces, which can then be inadvertently ingested by humans, especially children who play in areas where dogs are commonly walked. The ingestion of these eggs can lead to a condition known as toxocariasis.

Toxocariasis can cause a variety of symptoms, ranging from mild to severe. In some cases, it can lead to a condition called visceral larva migrans (VLM), where the larvae from the eggs migrate through the body, potentially affecting various organs. One of the more serious complications of VLM is the potential for the larvae to reach the eyes, which can cause inflammation and damage to the retina. This is known as ocular toxocariasis.

Ocular toxocariasis is relatively rare but can lead to significant vision problems, including partial blindness. The larvae can cause inflammation in the eye, which can result in scarring and the formation of a cyst. This can impair vision and, in severe cases, lead to blindness. It is estimated that over 100 cases of partial blindness in children are seen every year due to the presence of Toxocara canis eggs in feces.

It is important to note that the risk of contracting toxocariasis and the subsequent development of ocular toxocariasis is relatively low, especially with proper hygiene practices. However, it is still a significant concern, particularly for children who are more likely to play in areas where dog feces may be present and are also more likely to put their hands in their mouths.

Prevention is key in reducing the risk of toxocariasis. This includes:

1. Regular deworming of pets to reduce the number of eggs shed in feces.
2. Ensuring that children wash their hands thoroughly after playing outside, especially in areas where dogs are known to be walked.
3. Discouraging children from putting their hands in their mouths.
4. Regular cleaning of public areas to remove dog feces promptly.

In conclusion, while it is possible to contract toxocariasis from exposure to dog feces, leading to ocular toxocariasis and potentially partial blindness, the risk can be significantly reduced with proper hygiene and preventative measures. It is essential for both pet owners and parents to be aware of these risks and take the necessary steps to protect their children and pets.

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Again, possibly passing it on to humans, especially children playing in poo prevalent areas such as parks and woods. That dog poo can contain worms and their eggs. ... Over 100 cases of partial blindness in children are seen every year due to toxocara canis eggs in faeces.read more >>