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Parasite infection - endemic in 1st, 2nd, 3rd world countries - can and does present as asthma.

At one time, there were multiple papers available online, but many are much less available than previously.

One which is still available is here:

https://thorax.bmj.com/content/66/6/528

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Review
Parasitic infections of the lung: a guide for the respiratory physician
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H Kunst1, D Mack2, O M Kon3, A K Banerjee4, P Chiodini2,5, A Grant5

Correspondence to Heinke Kunst, Department of Respiratory Medicine, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, UK; hkunst@doctors.org.uk

Abstract

Parasitic infections of the lung occur worldwide among both immunocompetent and immunocompromised patients and may affect the respiratory system in a variety of ways. This review provides an update on the presenting symptoms, signs, investigation and management of diseases affecting the lung caused by protozoa, nematodes and trematodes. The clinical presentations and radiographic findings of several of these diseases may mimic tuberculosis and malignancy. It is important to consider parasitic infections in the differential diagnosis of such lung diseases. If identified early, most parasitic diseases that affect the lung are curable with medical or surgical treatments. . . .” . .

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Excerpt:

“Toxocariasis
Distribution and life cycle

Human toxocariasis is usually caused by the dog round worm Toxocara canis which commonly infects juvenile dogs and has a worldwide distribution. Humans, who are incidental hosts, are usually infected by the ingestion of eggs. The disease primarily affects children, who acquire the infection through contact with soil contaminated with embryonated eggs. Fresh animal faeces are not infectious as the eggs require 2–3 weeks to embryonate in the soil. Ingested eggs hatch in the stomach. Larvae penetrate the mucosa of the gut and enter the mesenteric vessels from where they migrate to the lungs and other organs.
Presentation

Most infections occur in children and most are asymptomatic. Patients may present with immunologically-mediated symptoms including cough, dyspnoea and wheeze which may present as asthma or bronchitis. Presenting signs may include hepatomegaly, splenomegaly and ocular lesions.
Radiographic features

Radiological features may include transient localised changes or widespread patchy areas of consolidation.13
Laboratory diagnosis

Toxocara larvae do not develop into adults in the human host, so eggs are not passed in human faeces. Visceral larva migrans is characterised by persistent peripheral eosinophilia and leucocytosis. A high degree of eosinophilia in the differential cell count of bronchoalveolar lavage fluid may support the diagnosis.32 33 Serological tests are available at reference laboratories. Although positive Toxocara serology supports a diagnosis of visceral larva migrans, titres may remain elevated for years and other causes of illness should be considered.34 Children suspected of ingesting infective Toxocara eggs may be investigated with full blood count and Toxocara serology tests at baseline and at 3 months. In practice this is seldom required as, in many cases where dog faeces have been ingested, it is possible to establish that the sample is relatively fresh and thus not likely to contain embryonated eggs. Tissue biopsy is not required for the diagnosis of visceral larva migrans.
Management

Ocular disease is treated under the supervision of an ophthalmologist with local or systemic steroids. Anthelminthics are not usually given. Visceral larva migrans is treated with albendazole. Corticosteroids may be required in more severe cases.28. . .” . . .